#3884 Ensure NullValuePropertyMappingStrategy.SET_TO_DEFAULT initializes empty collection/map when target is null

Signed-off-by: TangYang <tangyang9464@163.com>

.github/FUNDING.yml

@@ -0,0 +1,2 @@
+github: mapstruct
+open_collective: mapstruct

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,45 @@
+name: Bug report
+description: Create a report and help us improve
+labels: ["bug"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Please fill in all required fields with as many details as possible.
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected behavior
+      description: |
+        Describe what you were expecting MapStruct to do
+      placeholder: |
+        Here you can also add the generated code that you would like MapStruct to generate
+  - type: textarea
+    id: actual
+    attributes:
+      label: Actual behavior
+      description: |
+        Describe what you observed MapStruct did instead
+      placeholder: |
+        Here you can also add the generated code that MapStruct generated
+  - type: textarea
+    id: steps
+    attributes:
+      label: Steps to reproduce the problem
+      description: |
+        - Share your mapping configuration
+        - An [MCVE (Minimal Complete Verifiable Example)](https://stackoverflow.com/help/minimal-reproducible-example) can be helpful to provide a complete reproduction case
+      placeholder: |
+        Share your MapStruct configuration
+    validations:
+      required: true
+  - type: input
+    id: mapstruct-version
+    attributes:
+      label: MapStruct Version
+      description: |
+        Which MapStruct version did you use?
+        Note: While you can obviously continue using older versions of MapStruct, it may well be that your bug is already fixed. If you're using an older version, please also try to reproduce the bug in the latest version of MapStruct before reporting it.
+      placeholder: ex. MapStruct 1.5.2
+    validations:
+      required: true

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,16 @@
+contact_links:
+  - name: MapStruct Discussions
+    url: https://github.com/mapstruct/mapstruct/discussions
+    about: Please use the MapStruct GitHub Discussions for open ended discussions and to reach out to the community.
+  - name: Stack Overflow
+    url: https://stackoverflow.com/questions/tagged/mapstruct
+    about: For questions about how to use MapStruct, consider asking your question on Stack Overflow, tagged [mapstruct].
+  - name: Documentation
+    url: https://mapstruct.org/documentation/stable/reference/html/
+    about: The MapStruct reference documentation.
+  - name: Gitter Chat
+    url: https://gitter.im/mapstruct/mapstruct-users
+    about: For realtime communication with the MapStruct community, consider writing in our Gitter chat room.
+  - name: MapStruct Examples
+    url: https://github.com/mapstruct/mapstruct-examples
+    about: Some examples of what can be achieved with MapStruct. (contributions are always welcome)

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,43 @@
+name: Feature Request
+description: Suggest an idea
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Please describe the use-case you have. This will better help us understand the context in which you're looking for a new feature.
+  - type: textarea
+    id: use-case
+    attributes:
+      label: Use case
+      description: |
+        Please describe the use-case you have. This will better help us understand the context in which you're looking for a new feature.
+      placeholder: Describe the use-case here
+    validations:
+      required: true
+  - type: textarea
+    id: solution
+    attributes:
+      label: Generated Code
+      description: |
+        Please describe the possible generated code you'd like to see in MapStruct generate.
+        Please note, it's not always easy to describe a good solution. Describing the use-case above is much more important to us.
+      placeholder: Describe the possible solution here.
+    validations:
+      required: false
+  - type: textarea
+    id: workarounds
+    attributes:
+      label: Possible workarounds
+      description: |
+        Please describe the possible workarounds you've implemented to work around the lacking functionality.
+      placeholder: Describe the possible workarounds here.
+    validations:
+      required: false
+  - type: input
+    id: mapstruct-version
+    attributes:
+      label: MapStruct Version
+      description: What MapStruct version and edition did you try?
+      placeholder: ex. MapStruct 1.5.2
+    validations:
+      required: false

.github/scripts/update-website.sh

@@ -0,0 +1,82 @@
+#!/bin/bash
+#
+# Copyright MapStruct Authors.
+#
+# Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+#
+
+# env vars:
+# VERSION
+# GH_BOT_EMAIL
+
+# This script has been inspired by the JReleaser update-website.sh (https://github.com/jreleaser/jreleaser/blob/main/.github/scripts/update-website.sh)
+set -e
+
+function computePlainVersion() {
+  echo $1 | sed 's/\([[:digit:]]*\)\.\([[:digit:]]*\)\.\([[:digit:]]*\).*/\1.\2.\3/'
+}
+
+function computeMajorMinorVersion() {
+  echo $1 | sed 's/\([[:digit:]]*\)\.\([[:digit:]]*\).*/\1.\2/'
+}
+
+function isStable() {
+  local PLAIN_VERSION=$(computePlainVersion $1)
+  if [ "${PLAIN_VERSION}" == "$1" ]; then
+      echo "yes"
+  else
+      echo "no"
+  fi
+}
+
+STABLE=$(isStable $VERSION)
+MAJOR_MINOR_VERSION=$(computeMajorMinorVersion $VERSION)
+
+DEV_VERSION=`grep devVersion config.toml |  sed 's/.*"\(.*\)"/\1/'`
+MAJOR_MINOR_DEV_VERSION=$(computeMajorMinorVersion $DEV_VERSION)
+STABLE_VERSION=`grep stableVersion config.toml |  sed 's/.*"\(.*\)"/\1/'`
+MAJOR_MINOR_STABLE_VERSION=$(computeMajorMinorVersion $STABLE_VERSION)
+
+echo "📝 Updating versions"
+
+SEDOPTION="-i"
+if [[ "$OSTYPE" == "darwin"* ]]; then
+  SEDOPTION="-i ''"
+fi
+
+sed $SEDOPTION -e "s/^devVersion = \"\(.*\)\"/devVersion = \"${VERSION}\"/g" config.toml
+
+if [ "${STABLE}" == "yes" ]; then
+  sed $SEDOPTION -e "s/^stableVersion = \"\(.*\)\"/stableVersion = \"${VERSION}\"/g" config.toml
+  if [ "${MAJOR_MINOR_STABLE_VERSION}" != ${MAJOR_MINOR_VERSION} ]; then
+    echo "📝 Updating new stable version"
+    # This means that we have a new stable version and we need to change the order of the releases.
+    sed $SEDOPTION -e "s/^order = \(.*\)/order = 500/g" data/releases/${MAJOR_MINOR_VERSION}.toml
+    NEXT_STABLE_ORDER=$((`ls -1 data/releases | wc -l` - 2))
+    sed $SEDOPTION -e "s/^order = \(.*\)/order = ${NEXT_STABLE_ORDER}/g" data/releases/${MAJOR_MINOR_STABLE_VERSION}.toml
+    git add data/releases/${MAJOR_MINOR_STABLE_VERSION}.toml
+  fi
+elif [ "${MAJOR_MINOR_DEV_VERSION}" != "${MAJOR_MINOR_VERSION}" ]; then
+  echo "📝 Updating new dev version"
+  # This means that we are updating for a new dev version, but the last dev version is not the one that we are doing.
+  # Therefore, we need to update add the new data configuration
+  cp data/releases/${MAJOR_MINOR_DEV_VERSION}.toml data/releases/${MAJOR_MINOR_VERSION}.toml
+  sed $SEDOPTION -e "s/^order = \(.*\)/order = 1000/g" data/releases/${MAJOR_MINOR_VERSION}.toml
+fi
+
+sed $SEDOPTION -e "s/^name = \"\(.*\)\"/name = \"${VERSION}\"/g" data/releases/${MAJOR_MINOR_VERSION}.toml
+sed $SEDOPTION -e "s/^releaseDate = \(.*\)/releaseDate = $(date +%F)/g" data/releases/${MAJOR_MINOR_VERSION}.toml
+git add data/releases/${MAJOR_MINOR_VERSION}.toml
+git add config.toml
+
+echo "📝 Updating distribution resources"
+tar -xf tmp/mapstruct-${VERSION}-dist.tar.gz --directory tmp
+rm -rf static/documentation/${MAJOR_MINOR_VERSION}
+cp -R tmp/mapstruct-${VERSION}/docs static/documentation/${MAJOR_MINOR_VERSION}
+mv static/documentation/${MAJOR_MINOR_VERSION}/reference/html/mapstruct-reference-guide.html static/documentation/${MAJOR_MINOR_VERSION}/reference/html/index.html
+git add static/documentation/${MAJOR_MINOR_VERSION}
+
+git config --global user.email "${GH_BOT_EMAIL}"
+git config --global user.name "GitHub Action"
+git commit -a -m "Releasing version ${VERSION}"
+git push

.github/workflows/java-ea.yml

@@ -0,0 +1,21 @@
+name: Java EA
+
+on: [push]
+
+env:
+  MAVEN_ARGS: -V -B --no-transfer-progress -Dhttp.keepAlive=false -Dmaven.wagon.http.pool=false -Dmaven.wagon.httpconnectionManager.ttlSeconds=120
+
+jobs:
+  test_jdk_ea:
+    name: 'Linux JDK EA'
+    runs-on: ubuntu-latest
+    steps:
+      - name: 'Checkout'
+        uses: actions/checkout@v4
+      - name: 'Set up JDK'
+        uses: oracle-actions/setup-java@v1
+        with:
+          website: jdk.java.net
+          release: EA
+      - name: 'Test'
+        run: ./mvnw ${MAVEN_ARGS} -Djacoco.skip=true install -DskipDistribution=true

.github/workflows/macos.yml

@@ -0,0 +1,20 @@
+name: Mac OS CI
+
+on: push
+
+env:
+  MAVEN_ARGS: -V -B --no-transfer-progress -Dhttp.keepAlive=false -Dmaven.wagon.http.pool=false -Dmaven.wagon.httpconnectionManager.ttlSeconds=120
+
+jobs:
+  mac:
+    name: 'Mac OS'
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: 'Set up JDK 21'
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'zulu'
+          java-version: 21
+      - name: 'Test'
+        run: ./mvnw ${MAVEN_ARGS} install

.github/workflows/main.yml

@@ -0,0 +1,60 @@
+name: CI
+
+on: [push, pull_request]
+
+env:
+  SONATYPE_USERNAME: ${{ secrets.SONATYPE_USERNAME }}
+  SONATYPE_PASSWORD: ${{ secrets.SONATYPE_PASSWORD }}
+  MAVEN_ARGS: -V -B --no-transfer-progress -Dhttp.keepAlive=false -Dmaven.wagon.http.pool=false -Dmaven.wagon.httpconnectionManager.ttlSeconds=120
+
+jobs:
+  test_jdk:
+    strategy:
+      fail-fast: false
+      matrix:
+        java: [21]
+    name: 'Linux JDK ${{ matrix.java }}'
+    runs-on: ubuntu-latest
+    steps:
+      - name: 'Checkout'
+        uses: actions/checkout@v4
+      - name: 'Set up JDK'
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'zulu'
+          java-version: ${{ matrix.java }}
+      - name: 'Test'
+        run: ./mvnw ${MAVEN_ARGS} -Djacoco.skip=${{ matrix.java != 21 }} install -DskipDistribution=${{ matrix.java != 21 }}
+      - name: 'Generate coverage report'
+        if: matrix.java == 21
+        run: ./mvnw jacoco:report
+      - name: 'Upload coverage to Codecov'
+        if: matrix.java == 21
+        uses: codecov/codecov-action@v2
+      - name: 'Publish Snapshots'
+        if: matrix.java == 21 && github.event_name == 'push' && github.ref == 'refs/heads/main' && github.repository == 'mapstruct/mapstruct'
+        run: ./mvnw -s etc/ci-settings.xml -DskipTests=true -DskipDistribution=true deploy
+  integration_test_jdk:
+    strategy:
+      fail-fast: false
+      matrix:
+        java: [ 8, 11, 17 ]
+    name: 'Linux JDK ${{ matrix.java }}'
+    runs-on: ubuntu-latest
+    steps:
+      - name: 'Checkout'
+        uses: actions/checkout@v4
+      - name: 'Set up JDK 21 for building everything'
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'zulu'
+          java-version: 21
+      - name: 'Install Processor'
+        run: ./mvnw ${MAVEN_ARGS} -DskipTests install -pl processor -am
+      - name: 'Set up JDK ${{ matrix.java }} for running integration tests'
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'zulu'
+          java-version: ${{ matrix.java }}
+      - name: 'Run integration tests'
+        run: ./mvnw ${MAVEN_ARGS} verify -pl integrationtest

.github/workflows/release.yml

@@ -0,0 +1,117 @@
+name: Release
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'Release version'
+        required: true
+      next:
+        description: 'Next version'
+        required: false
+
+jobs:
+  release:
+    # This job has been inspired by the moditect release (https://github.com/moditect/moditect/blob/main/.github/workflows/release.yml)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Setup Java
+        uses: actions/setup-java@v4
+        with:
+          java-version: 21
+          distribution: 'zulu'
+          cache: maven
+
+      - name: Set release version
+        id: version
+        run: |
+          RELEASE_VERSION=${{ github.event.inputs.version }}
+          NEXT_VERSION=${{ github.event.inputs.next }}
+          PLAIN_VERSION=`echo ${RELEASE_VERSION} | awk 'match($0, /^(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)/) { print substr($0, RSTART, RLENGTH); }'`
+          COMPUTED_NEXT_VERSION="${PLAIN_VERSION}-SNAPSHOT"
+          if [ -z $NEXT_VERSION ]
+          then
+            NEXT_VERSION=$COMPUTED_NEXT_VERSION
+          fi
+          ./mvnw -ntp -B versions:set versions:commit -DnewVersion=$RELEASE_VERSION -pl :mapstruct-parent -DgenerateBackupPoms=false
+          git config --global user.email "${{ vars.GH_BOT_EMAIL }}"
+          git config --global user.name "GitHub Action"
+          git commit -a -m "Releasing version $RELEASE_VERSION"
+          git push
+          echo "RELEASE_VERSION=$RELEASE_VERSION" >> $GITHUB_ENV
+          echo "NEXT_VERSION=$NEXT_VERSION" >> $GITHUB_ENV
+          echo "PLAIN_VERSION=$PLAIN_VERSION" >> $GITHUB_ENV
+
+      - name: Stage
+        run: |
+          export GPG_TTY=$(tty)
+          ./mvnw -ntp -B --file pom.xml \
+            -Dmaven.site.skip=true -Drelease=true -Ppublication,stage
+
+      - name: Release
+        env:
+          JRELEASER_GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          JRELEASER_GPG_PASSPHRASE: ${{ secrets.GPG_PASSPHRASE }}
+          JRELEASER_GPG_PUBLIC_KEY: ${{ secrets.GPG_PUBLIC_KEY }}
+          JRELEASER_GPG_SECRET_KEY: ${{ secrets.GPG_PRIVATE_KEY }}
+          JRELEASER_NEXUS2_MAVEN_CENTRAL_USERNAME: ${{ secrets.SONATYPE_USERNAME }}
+          JRELEASER_NEXUS2_MAVEN_CENTRAL_PASSWORD: ${{ secrets.SONATYPE_PASSWORD }}
+        run: |
+          ./mvnw -ntp -B --file pom.xml -pl :mapstruct-parent -Pjreleaser jreleaser:release
+
+      - name: JReleaser output
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: jreleaser-release
+          path: |
+            parent/target/jreleaser/trace.log
+            parent/target/jreleaser/output.properties
+
+      - name: Reset NEXT_RELEASE_CHANGELOG.md
+        run: |
+          echo -e "### Features\n\n### Enhancements\n\n### Bugs\n\n### Documentation\n\n### Build\n" > NEXT_RELEASE_CHANGELOG.md
+
+      - name: Set next version
+        run: |
+          ./mvnw -ntp -B versions:set versions:commit -DnewVersion=${{ env.NEXT_VERSION }} -pl :mapstruct-parent -DgenerateBackupPoms=false
+          sed -i -e "s@project.build.outputTimestamp>.*</project.build.outputTimestamp@project.build.outputTimestamp>\${git.commit.author.time}</project.build.outputTimestamp@g" parent/pom.xml
+          git config --global user.email "${{ vars.GH_BOT_EMAIL }}"
+          git config --global user.name "GitHub Action"
+          git commit -a -m "Next version ${{ env.NEXT_VERSION }}"
+          git push
+
+  update-website:
+    # This job has been inspired by the JReleaser update-website job (https://github.com/jreleaser/jreleaser/blob/main/.github/workflows/release.yml)
+    name: Update Website
+    needs: [release]
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          repository: mapstruct/mapstruct.org
+          ref: main
+          fetch-depth: 0
+          token: ${{ secrets.GIT_WEBSITE_ACCESS_TOKEN }}
+
+      - name: Download assets
+        shell: bash
+        run: |
+          curl -sL https://raw.githubusercontent.com/mapstruct/mapstruct/main/.github/scripts/update-website.sh --output update-website.sh --create-dirs --output-dir tmp
+          curl -sL "https://github.com/mapstruct/mapstruct/releases/download/${VERSION}/mapstruct-${VERSION}-dist.tar.gz" --output mapstruct-${VERSION}-dist.tar.gz --create-dirs --output-dir tmp
+        env:
+          VERSION: ${{ github.event.inputs.version }}
+
+      - name: Commit
+        shell: bash
+        env:
+          VERSION: ${{ github.event.inputs.version }}
+          GH_BOT_EMAIL: ${{ vars.GH_BOT_EMAIL }}
+        run: |
+          chmod +x tmp/update-website.sh
+          tmp/update-website.sh

.github/workflows/windows.yml

@@ -0,0 +1,20 @@
+name: Windows CI
+
+on: push
+
+env:
+  MAVEN_ARGS: -V -B --no-transfer-progress -Dhttp.keepAlive=false -Dmaven.wagon.http.pool=false -Dmaven.wagon.httpconnectionManager.ttlSeconds=120
+
+jobs:
+  windows:
+    name: 'Windows'
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: 'Set up JDK 21'
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'zulu'
+          java-version: 21
+      - name: 'Test'
+        run: ./mvnw %MAVEN_ARGS% install

.gitignore

@@ -23,3 +23,5 @@ test-output
 
 # Misc.
 .DS_Store
+checkstyle.cache
+.flattened-pom.xml

.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,19 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+wrapperVersion=3.3.2
+distributionType=only-script
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.9/apache-maven-3.9.9-bin.zip

.travis.yml

@@ -1,23 +0,0 @@
-language: java
-jdk:
-  - oraclejdk8
-install: true
-script: mvn clean install -DprocessorIntegrationTest.toolchainsFile=etc/toolchains-travis-jenkins.xml -B -V
-after_success:
-  - mvn jacoco:report && bash <(curl -s https://codecov.io/bash) || echo "Codecov did not collect coverage reports"
-
-deploy:
-  provider: script
-  script: "test ${TRAVIS_TEST_RESULT} -eq 0 && mvn -s etc/travis-settings.xml -DskipTests=true deploy"
-  skip_cleanup: true
-  on:
-    branch: master
-
-sudo: required
-cache:
-  directories:
-  - $HOME/.m2
-addons:
-  apt:
-    packages:
-      - oracle-java8-installer

CONTRIBUTING.md

@@ -5,7 +5,7 @@ You love MapStruct but miss a certain feature? You found a bug and want to repor
 * Source code: [http://github.com/mapstruct/mapstruct](http://github.com/mapstruct/mapstruct)
 * Issue tracker: [https://github.com/mapstruct/mapstruct/issues](https://github.com/mapstruct/mapstruct/issues)
 * Discussions: Join the [mapstruct-users](https://groups.google.com/forum/?fromgroups#!forum/mapstruct-users) Google group
-* CI build: [https://travis-ci.org/mapstruct/mapstruct/](https://travis-ci.org/mapstruct/mapstruct/)
+* CI build: [https://github.com/mapstruct/mapstruct/actions/](https://github.com/mapstruct/mapstruct/actions)
 
 MapStruct follows the _Fork & Pull_ development approach. To get started just fork the [MapStruct repository](http://github.com/mapstruct/mapstruct) to your GitHub account and create a new topic branch for each change. Once you are done with your change, submit a [pull request](https://help.github.com/articles/using-pull-requests) against the MapStruct repo.
 

ISSUE_TEMPLATE.md

@@ -1,9 +0,0 @@
-- [ ] Is this an issue (and hence not a question)? 
-
-If this is a question how to use MapStruct there are several resources available.
-- Our reference- and API [documentation](http://mapstruct.org/documentation/reference-guide/).
-- Our [examples](https://github.com/mapstruct/mapstruct-examples) repository (contributions always welcome)
-- Our [FAQ](http://mapstruct.org/faq/)
-- [StackOverflow](https://stackoverflow.com), tag MapStruct 
-- [Gitter](https://gitter.im/mapstruct/mapstruct-users) (you usually get fast feedback)
-- Our [google group](https://groups.google.com/forum/#!forum/mapstruct-users)

NEXT_RELEASE_CHANGELOG.md

@@ -0,0 +1,29 @@
+### Features
+
+* Support for Java 21 Sequenced Collections (#3240)
+
+
+### Enhancements
+
+* Add support for locale parameter for numberFormat and dateFormat (#3628)
+* Detect Builder without a factory method (#3729) - With this if there is an inner class that ends with `Builder` and has a constructor with parameters, 
+it will be treated as a potential builder. 
+Builders through static methods on the type have a precedence.
+* Behaviour change: Warning when the target has no target properties (#1140)
+
+
+
+### Bugs
+
+* Improve error message when mapping non-iterable to array (#3786)
+
+### Documentation
+
+### Build
+
+### Behaviour Change
+
+#### Warning when the target has no target properties
+
+With this change, if the target bean does not have any target properties, a warning will be shown.
+This is like this to avoid potential mistakes by users, where they might think that the target bean has properties, but it does not.

build-config/pom.xml

@@ -12,7 +12,7 @@
     <parent>
         <groupId>org.mapstruct</groupId>
         <artifactId>mapstruct-parent</artifactId>
-        <version>1.4.0-SNAPSHOT</version>
+        <version>1.7.0-SNAPSHOT</version>
         <relativePath>../parent/pom.xml</relativePath>
     </parent>
 

build-config/src/main/resources/build-config/checkstyle.xml

@@ -15,6 +15,8 @@
         <property name="basedir" value="${basedir}"/>
     -->
 
+    <property name="cacheFile" value="${checkstyle.cache.file}"/>
+
     <!-- Checks that each Java package has a Javadoc file used for commenting. -->
     <!-- See http://checkstyle.sf.net/config_javadoc.html#JavadocPackage       -->
     <!--
@@ -27,7 +29,16 @@
     <!-- See http://checkstyle.sf.net/config_misc.html#Translation -->
     <module name="Translation"/>
 
-    <module name="FileLength"/>
+    <module name="FileLength">
+        <property name="max" value="2500"/>
+    </module>
+
+    <module name="LineLength">
+        <property name="max" value="120"/>
+        <property name="fileExtensions" value="java" />
+    </module>
+
+    <module name="SuppressWithPlainTextCommentFilter"/>
 
     <!-- Following interprets the header file as regular expressions. -->
     <!-- <module name="RegexpHeader"/>                                -->
@@ -60,8 +71,6 @@
 
     <module name="TreeWalker">
 
-        <property name="cacheFile" value="${checkstyle.cache.file}"/>
-
         <module name="SuppressWarningsHolder"/>
 
         <!-- Checks for Javadoc comments.                     -->
@@ -115,10 +124,6 @@
 
         <!-- Checks for Size Violations.                    -->
         <!-- See http://checkstyle.sf.net/config_sizes.html -->
-        <module name="LineLength">
-            <property name="max" value="120"/>
-        </module>
-        <module name="MethodLength"/>
         <module name="ParameterNumber">
             <property name="max" value="10"/>
         </module>
@@ -141,7 +146,9 @@
         </module>
         <module name="TypecastParenPad"/>
         <module name="WhitespaceAfter"/>
-        <module name="WhitespaceAround"/>
+        <module name="WhitespaceAround">
+            <property name="ignoreEnhancedForColon" value="false"/>
+        </module>
 
         <module name="EmptyLineSeparator">
             <property name="tokens" value="IMPORT, CLASS_DEF, INTERFACE_DEF, STATIC_INIT, INSTANCE_INIT, METHOD_DEF, CTOR_DEF, VARIABLE_DEF"/>

build-config/src/main/resources/build-config/import-control.xml

@@ -10,8 +10,8 @@
         <!-- the annotation processor may not use the annotations or enums specified in org.mapstruct directly... -->
         <disallow pkg="org.mapstruct" exact-match="true" />
 
-        <subpackage name="internal.prism">
-            <!-- ... with exception to the package org.mapstruct.ap.internal.prism -->
+        <subpackage name="internal.gem">
+            <!-- ... with exception to the package org.mapstruct.ap.internal.gem -->
             <allow pkg=".*" regex="true" /> 
         </subpackage>
         <subpackage name="test">

copyright.txt

@@ -2,10 +2,14 @@
 ============
 
 Alexandr Shalugin - https://github.com/shalugin
+Amine Touzani - https://github.com/ttzn
 Andreas Gudian - https://github.com/agudian
+Andrei Arlou - https://github.com/Captain1653
 Andres Jose Sebastian Rincon Gonzalez - https://github.com/stianrincon
 Arne Seime - https://github.com/seime
 Christian Bandowski - https://github.com/chris922
+Chris DeLashmutt - https://github.com/cdelashmutt-pivotal
+Christian Kosmowski - https://github.com/ckosmowski
 Christian Schuster - https://github.com/chschu
 Christophe Labouisse - https://github.com/ggtools
 Ciaran Liedeman - https://github.com/cliedeman
@@ -13,21 +17,35 @@ Cindy Wang - https://github.com/birdfriend
 Cornelius Dirmeier - https://github.com/cornzy
 David Feinblum - https://github.com/dvfeinblum
 Darren Rambaud - https://github.com/xyzst
+Dekel Pilli - https://github.com/dekelpilli
 Dilip Krishnan - https://github.com/dilipkrish
 Dmytro Polovinkin - https://github.com/navpil
+Ewald Volkert - https://github.com/eforest
 Eric Martineau - https://github.com/ericmartineau
 Ewald Volkert - https://github.com/eforest
 Filip Hrisafov - https://github.com/filiphr
 Florian Tavares - https://github.com/neoXfire
 Gervais Blaise - https://github.com/gervaisb
+Gibou Damien - https://github.com/dmngb
 Gunnar Morling - https://github.com/gunnarmorling
 Ivo Smid - https://github.com/bedla
+Jason Bodnar - https://github.com/Blackbaud-JasonBodnar
+Jeroen van Wilgenburg - https://github.com/jvwilge
 Jeff Smyth - https://github.com/smythie86
+João Paulo Bassinello - https://github.com/jpbassinello
+Jonathan Kraska - https://github.com/jakraska
 Joshua Spoerri - https://github.com/spoerri
+Jude Niroshan - https://github.com/JudeNiroshan
+Justyna Kubica-Ledzion - https://github.com/JKLedzion
+Kemal Özcan - https://github.com/yekeoe
 Kevin Grüneberg - https://github.com/kevcodez
+Lukas Lazar - https://github.com/LukeLaz
+Nikolas Charalambidis - https://github.com/Nikolas-Charalambidis
 Michael Pardo - https://github.com/pardom
+Muhammad Usama - https://github.com/the-mgi
 Mustafa Caylak - https://github.com/luxmeter
 Oliver Ehrenmüller - https://github.com/greuelpirat
+Oliver Erhart - https://github.com/thunderhook
 Paul Strugnell - https://github.com/ps-powa
 Pascal Grün - https://github.com/pascalgn
 Pavel Makhov - https://github.com/streetturtle
@@ -43,7 +61,13 @@ Sean Huang - https://github.com/seanjob
 Sjaak Derksen - https://github.com/sjaakd
 Stefan May - https://github.com/osthus-sm
 Taras Mychaskiw - https://github.com/twentylemon
+Thibault Duperron - https://github.com/Zomzog
+Tomáš Poledný - https://github.com/Saljack
+Tobias Meggendorfer - https://github.com/incaseoftrouble
 Tillmann Gaida - https://github.com/Tillerino
 Timo Eckhardt - https://github.com/timoe
 Tomek Gubala - https://github.com/vgtworld
+Valentin Kulesh - https://github.com/unshare
 Vincent Alexander Beelte - https://github.com/grandmasterpixel
+Winter Andreas - https://github.dev/wandi34
+Xiu Hong Kooi - https://github.com/kooixh

core-jdk8/pom.xml

@@ -12,7 +12,7 @@
     <parent>
         <groupId>org.mapstruct</groupId>
         <artifactId>mapstruct-parent</artifactId>
-        <version>1.4.0-SNAPSHOT</version>
+        <version>1.7.0-SNAPSHOT</version>
         <relativePath>../parent/pom.xml</relativePath>
     </parent>
 

core/pom.xml

@@ -12,7 +12,7 @@
     <parent>
         <groupId>org.mapstruct</groupId>
         <artifactId>mapstruct-parent</artifactId>
-        <version>1.4.0-SNAPSHOT</version>
+        <version>1.7.0-SNAPSHOT</version>
         <relativePath>../parent/pom.xml</relativePath>
     </parent>
 
@@ -22,8 +22,8 @@
 
     <dependencies>
         <dependency>
-            <groupId>junit</groupId>
-            <artifactId>junit</artifactId>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
             <scope>test</scope>
         </dependency>
         <dependency>

core/src/main/java/org/mapstruct/AnnotateWith.java

@@ -0,0 +1,176 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.Annotation;
+import java.lang.annotation.Repeatable;
+import java.lang.annotation.Retention;
+import java.lang.annotation.Target;
+
+import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
+import static java.lang.annotation.ElementType.METHOD;
+import static java.lang.annotation.ElementType.TYPE;
+import static java.lang.annotation.RetentionPolicy.CLASS;
+
+/**
+ * This can be used to have mapstruct generate additional annotations on classes/methods.
+ * <p>
+ * Examples based on the spring framework annotations.
+ * </p>
+ * Marking a class as `Lazy`:
+ *
+ * <pre><code>
+ * &#64;AnnotateWith( value = Lazy.class )
+ * &#64;Mapper
+ * public interface FooMapper {
+ *     // mapper code
+ * }
+ * </code></pre>
+ *
+ * The following code would be generated:
+ *
+ * <pre><code>
+ * &#64;Lazy
+ * public class FooMapperImpl implements FooMapper {
+ *     // mapper code
+ * }
+ * </code></pre>
+ * Setting the profile on the generated implementation:
+ *
+ * <pre><code>
+ * &#64;AnnotateWith( value = Profile.class, elements = @AnnotateWith.Element( strings = "prod" ) )
+ * &#64;Mapper
+ * public interface FooMapper {
+ *     // mapper code
+ * }
+ * </code></pre>
+ *
+ * The following code would be generated:
+ *
+ * <pre><code>
+ * &#64;Profile( value = "prod" )
+ * public class FooMapperImpl implements FooMapper {
+ *     // mapper code
+ * }
+ * </code></pre>
+ *
+ * @author Ben Zegveld
+ * @since 1.6
+ */
+@Repeatable( AnnotateWiths.class )
+@Retention( CLASS )
+@Target( { TYPE, METHOD, ANNOTATION_TYPE } )
+public @interface AnnotateWith {
+    /**
+     * @return the annotation class that needs to be added.
+     */
+    Class<? extends Annotation> value();
+
+    /**
+     * @return the annotation elements that are to be applied to this annotation.
+     */
+    Element[] elements() default {};
+
+    /**
+     * Used in combination with {@link AnnotateWith} to configure the annotation elements. Only 1 value type may be used
+     * within the same annotation at a time. For example mixing shorts and ints is not allowed.
+     *
+     * @author Ben Zegveld
+     * @since 1.6
+     */
+    @interface Element {
+        /**
+         * @return name of the annotation element.
+         */
+        String name() default "value";
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return short value(s) for the annotation element.
+         */
+        short[] shorts() default {};
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return byte value(s) for the annotation element.
+         */
+        byte[] bytes() default {};
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return int value(s) for the annotation element.
+         */
+        int[] ints() default {};
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return long value(s) for the annotation element.
+         */
+        long[] longs() default {};
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return float value(s) for the annotation element.
+         */
+        float[] floats() default {};
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return double value(s) for the annotation element.
+         */
+        double[] doubles() default {};
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return char value(s) for the annotation element.
+         */
+        char[] chars() default {};
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return boolean value(s) for the annotation element.
+         */
+        boolean[] booleans() default {};
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return string value(s) for the annotation element.
+         */
+        String[] strings() default {};
+
+        /**
+         * cannot be used in conjunction with other value fields.
+         *
+         * @return class value(s) for the annotation element.
+         */
+        Class<?>[] classes() default {};
+
+        /**
+         * only used in conjunction with the {@link #enums()} annotation element.
+         *
+         * @return the class of the enum.
+         */
+        Class<? extends Enum<?>> enumClass() default NullEnum.class;
+
+        /**
+         * cannot be used in conjunction with other value fields. {@link #enumClass()} is also required when using
+         * {@link #enums()}
+         *
+         * @return enum value(s) for the annotation element.
+         */
+        String[] enums() default {};
+
+    }
+}

core/src/main/java/org/mapstruct/AnnotateWiths.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.Target;
+
+import static java.lang.annotation.ElementType.METHOD;
+import static java.lang.annotation.ElementType.TYPE;
+import static java.lang.annotation.RetentionPolicy.CLASS;
+
+/**
+ * This can be used to have mapstruct generate additional annotations on classes/methods.
+ *
+ * @author Ben Zegveld
+ * @since 1.6
+ */
+@Retention( CLASS )
+@Target( { TYPE, METHOD } )
+public @interface AnnotateWiths {
+
+    /**
+     * The configuration of the additional annotations.
+     *
+     * @return The configuration of the additional annotations.
+     */
+    AnnotateWith[] value();
+}

core/src/main/java/org/mapstruct/BeanMapping.java

@@ -11,13 +11,46 @@ import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
+import org.mapstruct.control.MappingControl;
+
 import static org.mapstruct.NullValueCheckStrategy.ON_IMPLICIT_CONVERSION;
+import static org.mapstruct.SubclassExhaustiveStrategy.COMPILE_ERROR;
 
 /**
  * Configures the mapping between two bean types.
  * <p>
+ * Unless otherwise specified these properties are inherited to the generated bean mapping methods.
+ * <p>
  * Either {@link #resultType()}, {@link #qualifiedBy()} or {@link #nullValueMappingStrategy()} must be specified.
  * </p>
+ * <p><strong>Example:</strong> Determining the result type</p>
+ * <pre><code class='java'>
+ * // When result types have an inheritance relation, selecting either mapping method {@link Mapping} or factory method
+ * // {@link BeanMapping} can be become ambiguous. Parameter  {@link BeanMapping#resultType()} can be used.
+ * public class FruitFactory {
+ *     public Apple createApple() {
+ *         return new Apple();
+ *     }
+ *     public Orange createOrange() {
+ *         return new Orange();
+ *     }
+ * }
+ * &#64;Mapper(uses = FruitFactory.class)
+ * public interface FruitMapper {
+ *     &#64;BeanMapping(resultType = Apple.class)
+ *     Fruit toFruit(FruitDto fruitDto);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * public class FruitMapperImpl implements FruitMapper {
+ *      &#64;Override
+ *      public Fruit toFruit(FruitDto fruitDto) {
+ *          Apple fruit = fruitFactory.createApple();
+ *          // ...
+ *      }
+ * }
+ * </code></pre>
  *
  * @author Sjaak Derksen
  */
@@ -27,6 +60,8 @@ public @interface BeanMapping {
 
     /**
      * Specifies the result type of the factory method to be used in case several factory methods qualify.
+     * <p>
+     * <b>NOTE</b>: This property is not inherited to generated mapping methods
      *
      * @return the resultType to select
      */
@@ -40,9 +75,9 @@ public @interface BeanMapping {
      * A qualifier is a custom annotation and can be placed on either a hand written mapper class or a method.
      *
      * @return the qualifiers
-     * @see BeanMapping#qualifiedByName()
+     * @see Qualifier
      */
-    Class<? extends Annotation>[] qualifiedBy() default { };
+    Class<? extends Annotation>[] qualifiedBy() default {};
 
     /**
      * Similar to {@link #qualifiedBy()}, but used in combination with {@code @}{@link Named} in case no custom
@@ -86,9 +121,32 @@ public @interface BeanMapping {
      */
     NullValueCheckStrategy nullValueCheckStrategy() default ON_IMPLICIT_CONVERSION;
 
+    /**
+     * Determines how to handle missing implementation for super classes when using the {@link SubclassMapping}.
+     *
+     * Overrides the setting on {@link MapperConfig} and {@link Mapper}.
+     *
+     * @return strategy to handle missing implementation combined with {@link SubclassMappings}.
+     *
+     * @since 1.5
+     */
+    SubclassExhaustiveStrategy subclassExhaustiveStrategy() default COMPILE_ERROR;
+
+    /**
+     * Specifies the exception type to be thrown when a missing subclass implementation is detected
+     * in combination with {@link SubclassMappings}, based on the {@link #subclassExhaustiveStrategy()}.
+     * <p>
+     * This exception will only be thrown when the {@code subclassExhaustiveStrategy} is set to
+     * {@link SubclassExhaustiveStrategy#RUNTIME_EXCEPTION}.
+     *
+     * @return the exception class to throw when missing implementations are found.
+     *         Defaults to {@link IllegalArgumentException}.
+     */
+    Class<? extends Exception> subclassExhaustiveException() default IllegalArgumentException.class;
+
     /**
      * Default ignore all mappings. All mappings have to be defined manually. No automatic mapping will take place. No
-     * warning will be issued on missing target properties.
+     * warning will be issued on missing source or target properties.
      *
      * @return The ignore strategy (default false).
      *
@@ -103,6 +161,8 @@ public @interface BeanMapping {
      * source properties report.
      * <p>
      * <b>NOTE</b>: This does not support ignoring nested source properties
+     * <p>
+     * <b>NOTE</b>: This property is not inherited to generated mapping methods
      *
      * @return The source properties that should be ignored when performing a report
      *
@@ -110,6 +170,28 @@ public @interface BeanMapping {
      */
     String[] ignoreUnmappedSourceProperties() default {};
 
+    /**
+     * How unmapped properties of the source type of a mapping should be reported.
+     * If no policy is configured, the policy given via {@link MapperConfig#unmappedSourcePolicy()} or
+     * {@link Mapper#unmappedSourcePolicy()} will be applied, using {@link ReportingPolicy#IGNORE} by default.
+     *
+     * @return The reporting policy for unmapped source properties.
+     *
+     * @since 1.6
+     */
+    ReportingPolicy unmappedSourcePolicy() default ReportingPolicy.IGNORE;
+
+    /**
+     * How unmapped properties of the target type of a mapping should be reported.
+     * If no policy is configured, the policy given via {@link MapperConfig#unmappedTargetPolicy()} or
+     * {@link Mapper#unmappedTargetPolicy()} will be applied, using {@link ReportingPolicy#WARN} by default.
+     *
+     * @return The reporting policy for unmapped target properties.
+     *
+     * @since 1.5
+     */
+    ReportingPolicy unmappedTargetPolicy() default ReportingPolicy.WARN;
+
     /**
      * The information that should be used for the builder mappings. This can be used to define custom build methods
      * for the builder strategy that one uses.
@@ -128,4 +210,18 @@ public @interface BeanMapping {
      * @since 1.3
      */
     Builder builder() default @Builder;
+
+    /**
+     * Allows detailed control over the mapping process.
+     *
+     * @return the mapping control
+     *
+     * @since 1.4
+     *
+     * @see org.mapstruct.control.DeepClone
+     * @see org.mapstruct.control.NoComplexMapping
+     * @see org.mapstruct.control.MappingControl
+     */
+    Class<? extends Annotation> mappingControl() default MappingControl.class;
+
 }

core/src/main/java/org/mapstruct/Builder.java

@@ -14,6 +14,32 @@ import org.mapstruct.util.Experimental;
 /**
  * Configuration of builders, e.g. the name of the final build method.
  *
+ * <p>
+ * <strong>Example:</strong> Using builder
+ * </p>
+ * <pre><code class='java'>
+ * // Mapper
+ * &#64;Mapper
+ * public interface SimpleBuilderMapper {
+ *      &#64;Mapping(target = "name", source = "fullName"),
+ *      &#64;Mapping(target = "job", constant = "programmer"),
+ *      SimpleImmutablePerson toImmutable(SimpleMutablePerson source);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * &#64;Override
+ * public SimpleImmutablePerson toImmutable(SimpleMutablePerson source) {
+ *      // name method can be changed with parameter {@link #buildMethod()}
+ *      Builder simpleImmutablePerson = SimpleImmutablePerson.builder();
+ *      simpleImmutablePerson.name( source.getFullName() );
+ *      simpleImmutablePerson.age( source.getAge() );
+ *      simpleImmutablePerson.address( source.getAddress() );
+ *      simpleImmutablePerson.job( "programmer" );
+ *      // ...
+ * }
+ * </code></pre>
+ *
  * @author Filip Hrisafov
  *
  * @since 1.3
@@ -29,4 +55,12 @@ public @interface Builder {
      * @return the method that needs to tbe invoked on the builder
      */
     String buildMethod() default "build";
+
+    /**
+     * Toggling builders on / off. Builders are sometimes used solely for unit testing (fluent testdata)
+     * MapStruct will need to use the regular getters /setters in that case.
+     *
+     * @return when true, no builder patterns will be applied
+     */
+    boolean disableBuilder() default false;
 }

core/src/main/java/org/mapstruct/CollectionMappingStrategy.java

@@ -7,6 +7,54 @@ package org.mapstruct;
 
 /**
  * Strategy for propagating the value of collection-typed properties from source to target.
+ * <p>
+ * In the table below, the dash {@code -} indicates a property name.
+ * Next, the trailing {@code s} indicates the plural form.
+ * The table explains the options and how they are applied to the presence / absence of a
+ * {@code set-s}, {@code add-} and / or {@code get-s} method on the target object.
+ * <table>
+ *     <caption>Collection mapping strategy options</caption>
+ *     <tr>
+ *         <th>Option</th>
+ *         <th>Only target set-s Available</th>
+ *         <th>Only target add- Available</th>
+ *         <th>Both set-s/add- Available</th>
+ *         <th>No set-s/add- Available</th>
+ *         <th>Existing Target ({@code @TargetType})</th>
+ *     </tr>
+ *     <tr>
+ *         <td>{@link #ACCESSOR_ONLY}</td>
+ *         <td>set-s</td>
+ *         <td>get-s</td>
+ *         <td>set-s</td>
+ *         <td>get-s</td>
+ *         <td>get-s</td>
+ *     </tr>
+ *     <tr>
+ *         <td>{@link #SETTER_PREFERRED}</td>
+ *         <td>set-s</td>
+ *         <td>add-</td>
+ *         <td>set-s</td>
+ *         <td>get-s</td>
+ *         <td>get-s</td>
+ *     </tr>
+ *     <tr>
+ *         <td>{@link #ADDER_PREFERRED}</td>
+ *         <td>set-s</td>
+ *         <td>add-</td>
+ *         <td>add-</td>
+ *         <td>get-s</td>
+ *         <td>get-s</td>
+ *     </tr>
+ *     <tr>
+ *         <td>{@link #TARGET_IMMUTABLE}</td>
+ *         <td>set-s</td>
+ *         <td>exception</td>
+ *         <td>set-s</td>
+ *         <td>exception</td>
+ *         <td>set-s</td>
+ *     </tr>
+ * </table>
  *
  * @author Sjaak Derksen
  */

core/src/main/java/org/mapstruct/Condition.java

@@ -0,0 +1,96 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * This annotation marks a method as a <em>presence check method</em> to check for presence in beans
+ * or it can be used to define additional check methods for something like source parameters.
+ * <p>
+ * By default, bean properties are checked against {@code null} or using a presence check method in the source bean.
+ * If a presence check method is available then it will be used instead.
+ * <p>
+ * Presence check methods have to return {@code boolean}.
+ * The following parameters are accepted for the presence check methods:
+ *     <ul>
+ *         <li>The parameter with the value of the source property.
+ *         e.g. the value given by calling {@code getName()} for the name property of the source bean
+ *         - only possible when using the {@link ConditionStrategy#PROPERTIES}
+ *         </li>
+ *         <li>The mapping source parameter</li>
+ *         <li>{@code @}{@link Context} parameter</li>
+ *         <li>
+ *             {@code @}{@link TargetPropertyName} parameter -
+ *             only possible when using the {@link ConditionStrategy#PROPERTIES}
+ *         </li>
+ *         <li>
+ *             {@code @}{@link SourcePropertyName} parameter -
+ *             only possible when using the {@link ConditionStrategy#PROPERTIES}
+ *         </li>
+ *     </ul>
+ *
+ * <strong>Note:</strong> The usage of this annotation is <em>mandatory</em>
+ * for a method to be considered as a presence check method.
+ *
+ * <pre><code class='java'>
+ * public class PresenceCheckUtils {
+ *
+ *   &#64;Condition
+ *   public static boolean isNotEmpty(String value) {
+ *      return value != null &#38;&#38; !value.isEmpty();
+ *   }
+ * }
+ *
+ * &#64;Mapper(uses = PresenceCheckUtils.class)
+ * public interface MovieMapper {
+ *
+ *     MovieDto map(Movie movie);
+ * }
+ * </code></pre>
+ * <p>
+ * The following implementation of {@code MovieMapper} will be generated:
+ *
+ * <pre><code class='java'>
+ * public class MovieMapperImpl implements MovieMapper {
+ *
+ *     &#64;Override
+ *     public MovieDto map(Movie movie) {
+ *         if ( movie == null ) {
+ *             return null;
+ *         }
+ *
+ *         MovieDto movieDto = new MovieDto();
+ *
+ *         if ( PresenceCheckUtils.isNotEmpty( movie.getTitle() ) ) {
+ *             movieDto.setTitle( movie.getTitle() );
+ *         }
+ *
+ *         return movieDto;
+ *     }
+ * }
+ * </code></pre>
+ * <p>
+ * This annotation can also be used as a meta-annotation to define the condition strategy.
+ *
+ * @author Filip Hrisafov
+ * @see SourceParameterCondition
+ * @since 1.5
+ */
+@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
+@Retention(RetentionPolicy.CLASS)
+public @interface Condition {
+
+    /**
+     * @return the places where the condition should apply to
+     * @since 1.6
+     */
+    ConditionStrategy[] appliesTo() default ConditionStrategy.PROPERTIES;
+
+}

core/src/main/java/org/mapstruct/ConditionStrategy.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+/**
+ * Strategy for defining what to what a condition (check) method is applied to
+ *
+ * @author Filip Hrisafov
+ * @since 1.6
+ */
+public enum ConditionStrategy {
+    /**
+     * The condition method should be applied whether a property should be mapped.
+     */
+    PROPERTIES,
+    /**
+     * The condition method should be applied to check if a source parameters should be mapped.
+     */
+    SOURCE_PARAMETERS,
+}

core/src/main/java/org/mapstruct/DecoratedWith.java

@@ -22,9 +22,7 @@ import java.lang.annotation.Target;
  * <p>
  * <b>NOTE:</b> This annotation is not supported for the component model {@code cdi}. Use CDI's own
  * <a href="https://docs.jboss.org/cdi/spec/1.0/html/decorators.html">{@code @Decorator}</a> feature instead.
- * <p>
- * <b>NOTE:</b> The decorator feature when used with component model {@code jsr330} is considered <em>experimental</em>
- * and it may change in future releases.
+ * </p>
  * <h2>Examples</h2>
  * <p>
  * For the examples below, consider the following mapper declaration:
@@ -105,12 +103,12 @@ import java.lang.annotation.Target;
  * private PersonMapper personMapper; // injects the decorator, with the injected original mapper
  * </pre>
  *
- * <h3>3. Component model 'jsr330'</h3>
+ * <h3>3. Component model 'jsr330' or 'jakarta'</h3>
  * <h4>Referencing the original mapper</h4>
  * <p>
- * JSR 330 doesn't specify qualifiers and only allows to specifically name the beans. Hence, the generated
- * implementation of the original mapper is annotated with
- * {@code @javax.inject.Named("fully-qualified-name-of-generated-impl")} and {@code @Singleton} (please note that when
+ * JSR 330 / Jakarta Inject doesn't specify qualifiers and only allows to specifically name the beans. Hence,
+ * the generated implementation of the original mapper is annotated with
+ * {@code @Named("fully-qualified-name-of-generated-impl")} and {@code @Singleton} (please note that when
  * using a decorator, the class name of the mapper implementation ends with an underscore). To inject that bean in your
  * decorator, add the same annotation to the delegate field (e.g. by copy/pasting it from the generated class):
  *
@@ -147,7 +145,7 @@ import java.lang.annotation.Target;
  * @author Gunnar Morling
  */
 @Target(ElementType.TYPE)
-@Retention(RetentionPolicy.SOURCE)
+@Retention(RetentionPolicy.CLASS)
 public @interface DecoratedWith {
 
     /**

core/src/main/java/org/mapstruct/EnumMapping.java

@@ -0,0 +1,156 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Configured the mapping between two value types.
+ * <p><strong>Example:</strong> Using a suffix for enums</p>
+ * <pre><code class='java'>
+ * public enum CheeseType {
+ *     BRIE,
+ *     ROQUEFORT
+ * }
+ *
+ * public enum CheeseTypeSuffixed {
+ *     BRIE_TYPE,
+ *     ROQUEFORT_TYPE
+ * }
+ *
+ * &#64;Mapper
+ * public interface CheeseMapper {
+ *
+ *     &#64;EnumMapping(nameTransformationStrategy = "suffix", configuration = "_TYPE")
+ *     CheeseTypeSuffixed map(Cheese cheese);
+ *
+ *     &#64;InheritInverseConfiguration
+ *     Cheese map(CheeseTypeSuffixed cheese);
+ *
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * public class CheeseMapperImpl implements CheeseMapper {
+ *
+ *     &#64;Override
+ *     public CheeseTypeSuffixed map(Cheese cheese) {
+ *         if ( cheese == null ) {
+ *             return null;
+ *         }
+ *
+ *         CheeseTypeSuffixed cheeseTypeSuffixed;
+ *
+ *         switch ( cheese ) {
+ *             case BRIE:
+ *                 cheeseTypeSuffixed = CheeseTypeSuffixed.BRIE_TYPE;
+ *                 break;
+ *             case ROQUEFORT:
+ *                 cheeseTypeSuffixed = CheeseTypeSuffixed.ROQUEFORT_TYPE;
+ *                 break;
+ *             default:
+ *                 throw new IllegalArgumentException( "Unexpected enum constant: " + cheese );
+ *         }
+ *
+ *         return cheeseTypeSuffixed;
+ *     }
+ *
+ *     &#64;Override
+ *     public Cheese map(CheeseTypeSuffixed cheese) {
+ *         if ( cheese == null ) {
+ *             return null;
+ *         }
+ *
+ *         CheeseType cheeseType;
+ *
+ *         switch ( cheese ) {
+ *             case BRIE_TYPE:
+ *                 cheeseType = CheeseType.BRIE;
+ *                 break;
+ *             case ROQUEFORT_TYPE:
+ *                 cheeseType = CheeseType.ROQUEFORT;
+ *                 break;
+ *             default:
+ *                 throw new IllegalArgumentException( "Unexpected enum constant: " + cheese );
+ *         }
+ *
+ *         return cheeseType;
+ *     }
+ * }
+ * </code></pre>
+ *
+ * @author Filip Hrisafov
+ * @since 1.4
+ */
+@Target(ElementType.METHOD)
+@Retention(RetentionPolicy.CLASS)
+public @interface EnumMapping {
+
+    /**
+     * Specifies the name transformation strategy that should be used for implicit mapping between enums.
+     * Known strategies are:
+     * <ul>
+     *     <li>{@link MappingConstants#SUFFIX_TRANSFORMATION} - applies the given {@link #configuration()} as a
+     *     suffix to the source enum</li>
+     *     <li>{@link MappingConstants#STRIP_SUFFIX_TRANSFORMATION} - strips the given {@link #configuration()}
+     *     from the end of the source enum</li>
+     *     <li>{@link MappingConstants#PREFIX_TRANSFORMATION} - applies the given {@link #configuration()} as a
+     *     prefix to the source enum</li>
+     *     <li>{@link MappingConstants#STRIP_PREFIX_TRANSFORMATION} - strips the given {@link #configuration()} from
+     *     the start of the source enum</li>
+     *     <li>
+     *         {@link MappingConstants#CASE_TRANSFORMATION} - applies the given {@link #configuration()} case
+     *         transformation to the source enum. Supported configurations are:
+     *         <ul>
+     *             <li><i>upper</i> - Performs upper case transformation to the source enum</li>
+     *             <li><i>lower</i> - Performs lower case transformation to the source enum</li>
+     *             <li>
+     *                 <i>capital</i> - Performs capitalisation of the first character of every word in the source enum
+     *                 and everything else to lower case. A word is split by "_".
+     *             </li>
+     *         </ul>
+     *     </li>
+     * </ul>
+     *
+     * It is possible to use custom name transformation strategies by implementing the {@code
+     * EnumTransformationStrategy} SPI.
+     *
+     * @return the name transformation strategy
+     */
+    String nameTransformationStrategy() default "";
+
+    /**
+     * The configuration that should be passed on the appropriate name transformation strategy.
+     * e.g. a suffix that should be applied to the source enum when doing name based mapping.
+     *
+     * @return the configuration to use
+     */
+    String configuration() default "";
+
+    /**
+     * Exception that should be thrown by the generated code if no mapping matches.
+     * If no exception is configured, the exception given via {@link MapperConfig#unexpectedValueMappingException()} or
+     * {@link Mapper#unexpectedValueMappingException()} will be used, using {@link IllegalArgumentException} by default.
+     *
+     * <p>
+     * Note:
+     * <ul>
+     *     <li>
+     *      The defined exception should at least have a constructor with a {@link String} parameter.
+     *     </li>
+     *     <li>
+     *      If the defined exception is a checked exception then the enum mapping methods should have that exception
+     *      in the throws clause.
+     *     </li>
+     * </ul>
+     *
+     * @return the exception that should be used in the generated code
+     */
+    Class<? extends Exception> unexpectedValueMappingException() default IllegalArgumentException.class;
+}

core/src/main/java/org/mapstruct/Ignored.java

@@ -0,0 +1,67 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Repeatable;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Configures the ignored of one bean attribute.
+ *
+ * <p>
+ * The name all attributes of for ignored is to be specified via {@link #targets()}.
+ * </p>
+ *
+ * <p>
+ * <strong>Example 1:</strong> Implicitly mapping fields with the same name:
+ * </p>
+ *
+ * <pre><code class='java'>
+ * // We need ignored Human.name and Human.lastName
+ * // we can use &#64;Ignored with parameters "name", "lastName" {@link #targets()}
+ * &#64;Mapper
+ * public interface HumanMapper {
+ *    &#64;Ignored( targets = { "name", "lastName" } )
+ *    HumanDto toHumanDto(Human human)
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates:
+ * &#64;Override
+ * public HumanDto toHumanDto(Human human) {
+ *    humanDto.setFullName( human.getFullName() );
+ *    // ...
+ * }
+ * </code></pre>
+ *
+ * @author Ivashin Aleksey
+ */
+@Repeatable(IgnoredList.class)
+@Retention(RetentionPolicy.CLASS)
+@Target({ElementType.METHOD, ElementType.ANNOTATION_TYPE})
+public @interface Ignored {
+
+    /**
+     * Whether the specified properties should be ignored by the generated mapping method.
+     * This can be useful when certain attributes should not be propagated from source to target or when properties in
+     * the target object are populated using a decorator and thus would be reported as unmapped target property by
+     * default.
+     *
+     * @return The target names of the configured properties that should be ignored
+     */
+    String[] targets();
+
+    /**
+     * The prefix that should be applied to all the properties specified via {@link #targets()}.
+     *
+     * @return The target prefix to be applied to the defined properties
+     */
+    String prefix() default "";
+
+}

core/src/main/java/org/mapstruct/IgnoredList.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Configures the ignored list for several bean attributes.
+ * <p>
+ * <strong>TIP: When using Java 8 or later, you can omit the {@code @IgnoredList}
+ * wrapper annotation and directly specify several {@code @Ignored} annotations on one method.</strong>
+ *
+ * <p>These two examples are equal.
+ * </p>
+ * <pre><code class='java'>
+ * // before Java 8
+ * &#64;Mapper
+ * public interface MyMapper {
+ *     &#64;IgnoredList({
+ *         &#64;Ignored(targets = { "firstProperty" } ),
+ *         &#64;Ignored(targets = { "secondProperty" } )
+ *     })
+ *     HumanDto toHumanDto(Human human);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // Java 8 and later
+ * &#64;Mapper
+ * public interface MyMapper {
+ *     &#64;Ignored(targets = { "firstProperty" } ),
+ *     &#64;Ignored(targets = { "secondProperty" } )
+ *     HumanDto toHumanDto(Human human);
+ * }
+ * </code></pre>
+ *
+ * @author Ivashin Aleksey
+ */
+@Retention(RetentionPolicy.CLASS)
+@Target({ElementType.METHOD, ElementType.ANNOTATION_TYPE })
+public @interface IgnoredList {
+
+    /**
+     * The configuration of the bean attributes.
+     *
+     * @return The configuration of the bean attributes.
+     */
+    Ignored[] value();
+}

core/src/main/java/org/mapstruct/InheritConfiguration.java

@@ -18,6 +18,10 @@ import java.lang.annotation.Target;
  * If no method can be identified unambiguously as configuration source (i.e. several candidate methods with matching
  * source and target type exist), the name of the method to inherit from must be specified via {@link #name()}.
  * <p>
+ * {@link Mapping#expression()}, {@link Mapping#constant()}, {@link Mapping#defaultExpression()} and
+ * {@link Mapping#defaultValue()} are not inverse inherited
+ *
+ * <p>
  * A typical use case is annotating an update method so it inherits all mappings from a corresponding "standard" mapping
  * method:
  *

core/src/main/java/org/mapstruct/InheritInverseConfiguration.java

@@ -21,7 +21,59 @@ import java.lang.annotation.Target;
  * <p>
  * If more than one matching inverse method exists, the name of the method to inherit the configuration from must be
  * specified via {@link #name()}
+ * <p>
+ * {@link Mapping#expression()}, {@link Mapping#constant()}, {@link Mapping#defaultExpression()} and
+ * {@link Mapping#defaultValue()} are not inverse inherited
  *
+ * <p>
+ * <strong>Examples</strong>
+ * </p>
+ * <pre><code class='java'>
+ * &#64;Mapper
+ * public interface HumanMapper {
+ *      Human toHuman(HumanDto humanDto);
+ *      &#64;InheritInverseConfiguration
+ *      HumanDto toHumanDto(Human human);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * public class HumanMapperImpl implements HumanMapper {
+ *      &#64;Override
+ *      public Human toHuman(HumanDto humanDto) {
+ *          if ( humanDto == null ) {
+ *              return null;
+ *           }
+ *          Human human = new Human();
+ *          human.setName( humanDto.getName() );
+ *          return human;
+ *      }
+ *      &#64;Override
+ *      public HumanDto toHumanDto(Human human) {
+ *          if ( human == null ) {
+ *              return null;
+ *          }
+ *          HumanDto humanDto = new HumanDto();
+ *          humanDto.setName( human.getName() );
+ *          return humanDto;
+ *      }
+ * }
+ * </code></pre>
+ *
+ * <pre><code class='java'>
+ * &#64;Mapper
+ * public interface CarMapper {
+ *
+ * &#64;Mapping( target = "seatCount", source = "numberOfSeats")
+ * &#64;Mapping( target = "enginePower", source = "engineClass", ignore=true) // NOTE: source specified as well
+ * CarDto carToDto(Car car);
+ *
+ * &#64;InheritInverseConfiguration
+ * &#64;Mapping(target = "numberOfSeats", ignore = true)
+ * // no need to specify a mapping with ignore for "engineClass": specifying source above will assume
+ * Car carDtoToCar(CarDto carDto);
+ * }
+ * </code></pre>
  * @author Sjaak Derksen
  */
 @Target(ElementType.METHOD)
@@ -29,8 +81,8 @@ import java.lang.annotation.Target;
 public @interface InheritInverseConfiguration {
 
     /**
-     * The name of the inverse mapping method to inherit the mappings from. Needs only to be specified in case more than
-     * one inverse method with matching source and target type exists.
+     * The name of the inverse mapping method to inherit the mappings from. Needs to be specified only in case more than
+     * one inverse method exists with a matching source and target type exists.
      *
      * @return The name of the inverse mapping method to inherit the mappings from.
      */

core/src/main/java/org/mapstruct/InjectionStrategy.java

@@ -7,9 +7,10 @@ package org.mapstruct;
 
 /**
  * Strategy for handling injection. This is only used on annotated based component models such as CDI, Spring and
- * JSR330.
+ * JSR330 / Jakarta.
  *
  * @author Kevin Grüneberg
+ * @author Lucas Resch
  */
 public enum InjectionStrategy {
 
@@ -17,5 +18,8 @@ public enum InjectionStrategy {
     FIELD,
 
     /** Annotations are written on the constructor **/
-    CONSTRUCTOR
+    CONSTRUCTOR,
+
+    /** A dedicated setter method is created */
+    SETTER
 }

core/src/main/java/org/mapstruct/IterableMapping.java

@@ -10,17 +10,43 @@ import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
-import java.text.SimpleDateFormat;
 import java.text.DecimalFormat;
+import java.text.SimpleDateFormat;
 import java.util.Date;
 
+import org.mapstruct.control.MappingControl;
+
 /**
  * Configures the mapping between two iterable like types, e.g. {@code List<String>} and {@code List<Date>}.
  *
  *
- * <p>Note: either  @IterableMapping#dateFormat, @IterableMapping#resultType or @IterableMapping#qualifiedBy
+ * <p>Note: either  {@link #dateFormat()}, {@link #elementTargetType()} or {@link #qualifiedBy() }
  * must be specified</p>
  *
+ * <p>
+ * <strong>Example:</strong> Convert List&lt;Float&gt; to List&lt;String&gt;
+ * </p>
+ * <pre><code class='java'>
+ * &#64;Mapper
+ * public interface FloatToStringMapper {
+ *      &#64;IterableMapping( numberFormat = "##.00" )
+ *      List&lt;String&gt; sourceToTarget(List&lt;Float&gt; source);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * public class FloatToStringMapperImpl implements FloatToStringMapper {
+ *      &#64;Override
+ *      public List&lt;String&gt; sourceToTarget(List&lt;Float&gt; source) {
+ *          List&lt;String&gt; list = new ArrayList&lt;String&gt;( source.size() );
+ *          for ( Float float1 : source ) {
+ *              list.add( new DecimalFormat( "##.00" ).format( float1 ) );
+ *          }
+ *     // ...
+ *      }
+ * }
+ * </code></pre>
+ *
  * Supported mappings are:
  * <ul>
  *     <li>{@code Iterable<A>} to/from {@code Iterable<B>}/{@code Iterable<A>}</li>
@@ -40,19 +66,38 @@ public @interface IterableMapping {
     /**
      * A format string as processable by {@link SimpleDateFormat} if the annotated method maps from an iterable of
      * {@code String} to an iterable {@link Date} or vice-versa. Will be ignored for all other element types.
+     * <p>
+     * If the {@link #locale()} is also specified, the format will consider the specified locale when processing
+     * the date. Otherwise, the system's default locale will be used.
      *
      * @return A date format string as processable by {@link SimpleDateFormat}.
+     * @see #locale()
      */
     String dateFormat() default "";
 
     /**
      * A format string as processable by {@link DecimalFormat} if the annotated method maps from a
      *  {@link Number} to a {@link String} or vice-versa. Will be ignored for all other element types.
+     * <p>
+     * If the {@link #locale()} is also specified, the number format will be applied in the context of the given locale.
+     * Otherwise, the system's default locale will be used to process the number format.
      *
      * @return A decimal format string as processable by {@link DecimalFormat}.
+     * @see #locale()
      */
     String numberFormat() default "";
 
+    /**
+     * Specifies the locale to be used when processing {@link #dateFormat()} or {@link #numberFormat()}.
+     * <p>
+     * The locale should be a plain tag representing the language, such as "en" for English, "de" for German, etc.
+     * <p>
+     * If no locale is specified, the system's default locale will be used.
+     *
+     * @return A string representing the locale to be used when formatting dates or numbers.
+     */
+    String locale() default "";
+
     /**
      * A qualifier can be specified to aid the selection process of a suitable mapper. This is useful in case multiple
      * mappers (hand written of internal) qualify and result in an 'Ambiguous mapping methods found' error.
@@ -60,6 +105,7 @@ public @interface IterableMapping {
      * A qualifier is a custom annotation and can be placed on either a hand written mapper class or a method.
      *
      * @return the qualifiers
+     * @see Qualifier
      */
     Class<? extends Annotation>[] qualifiedBy() default { };
 
@@ -96,4 +142,18 @@ public @interface IterableMapping {
      * @return The strategy to be applied when {@code null} is passed as source value to the methods of this mapping.
      */
     NullValueMappingStrategy nullValueMappingStrategy() default NullValueMappingStrategy.RETURN_NULL;
+
+    /**
+     * Allows detailed control over the mapping process.
+     *
+     * @return the mapping control
+     *
+     * @since 1.4
+     *
+     * @see org.mapstruct.control.DeepClone
+     * @see org.mapstruct.control.NoComplexMapping
+     * @see org.mapstruct.control.MappingControl
+     */
+    Class<? extends Annotation> elementMappingControl() default MappingControl.class;
+
 }

core/src/main/java/org/mapstruct/Javadoc.java

@@ -0,0 +1,115 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Allows the definition of Javadoc comments in the MapStruct <code>Mapper</code> generated class.
+ *
+ * <p>The annotation provides support for the usual Javadoc comments elements by defining analogous attributes.</p>
+ *
+ *
+ * <p>Please, note that at least one of these attributes must be specified.</p>
+ *
+ * <p>
+ * For instance, the following definition;
+ * </p>
+ * <pre><code class='java'>
+ * &#64;Javadoc(
+ *     value = "This is the description",
+ *     authors = { "author1", "author2" },
+ *     deprecated = "Use {&#64;link OtherMapper} instead",
+ *     since = "0.1"
+ * )
+ * </code></pre>
+ *
+ * <p>
+ * will generate:
+ * </p>
+ *
+ * <pre><code class='java'>
+ * /**
+ * * This is the description
+ * *
+ * * &#64;author author1
+ * * &#64;author author2
+ * *
+ * * &#64;deprecated Use {&#64;link OtherMapper} instead
+ * * &#64;since 0.1
+ * *&#47;
+ * </code></pre>
+ *
+ * <p>
+ * The entire Javadoc comment block can be passed directly:
+ * </p>
+ * <pre><code class='java'>
+ * &#64;Javadoc("This is the description\n"
+ *            + "\n"
+ *            + "&#64;author author1\n"
+ *            + "&#64;author author2\n"
+ *            + "\n"
+ *            + "&#64;deprecated Use {&#64;link OtherMapper} instead\n"
+ *            + "&#64;since 0.1\n"
+ * )
+ * </code></pre>
+ *
+ * <pre><code class='java'>
+ * // or using Text Blocks
+ * &#64;Javadoc(
+ *     """
+ *     This is the description
+ *
+ *     &#64;author author1
+ *     &#64;author author2
+ *
+ *     &#64;deprecated Use {&#64;link OtherMapper} instead
+ *     &#64;since 0.1
+ *     """
+ * )
+ * </code></pre>
+ */
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.SOURCE)
+public @interface Javadoc {
+    /**
+     * Main Javadoc comment text block.
+     *
+     * @return Main Javadoc comment text block.
+     */
+    String value() default "";
+
+    /**
+     * List of authors of the code that it is being documented.
+     * <p>
+     * It will generate a list of the Javadoc tool comment element <code>&#64;author</code>
+     * with the different values and in the order provided.
+     *
+     * @return array of javadoc authors.
+     */
+    String[] authors() default { };
+
+    /**
+     * Specifies that the functionality that is being documented is deprecated.
+     * <p>
+     * Corresponds to the <code>&#64;deprecated</code> Javadoc tool comment element.
+     *
+     * @return Deprecation message about the documented functionality
+     */
+    String deprecated() default "";
+
+    /**
+     * Specifies the version since the functionality that is being documented is available.
+     * <p>
+     * Corresponds to the <code>&#64;since</code> Javadoc tool comment element.
+     *
+     * @return Version since the functionality is available
+     */
+    String since() default "";
+}

core/src/main/java/org/mapstruct/MapMapping.java

@@ -10,14 +10,42 @@ import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
-import java.text.SimpleDateFormat;
 import java.text.DecimalFormat;
+import java.text.SimpleDateFormat;
 import java.util.Date;
 
+import org.mapstruct.control.MappingControl;
+
 /**
- * Configures the mapping between two map types, e.g. {@code Map<String, String>} and {@code Map<Long, Date>}.
+ * Configures the mapping between two map types, e.g. Map&lt;String, String&gt; and Map&lt;Long, Date&gt;.
  *
- * <p>Note: at least one element needs to be specified</p>
+ * <p>
+ * <strong>Example</strong>:
+ * </p>
+ * <pre><code class='java'>
+ * &#64;Mapper
+ * public interface SimpleMapper {
+ *       &#64;MapMapping(valueDateFormat = "dd.MM.yyyy")
+ *       Map&lt;String, String&gt; longDateMapToStringStringMap(Map&lt;Long, Date&gt; source);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * public class SimpleMapperImpl implements SimpleMapper {
+ *      &#64;Override
+ *      public Map&lt;String, String&gt; longDateMapToStringStringMap(Map&lt;Long, Date&gt; source) } {
+ *          Map&lt;String, String&gt; map = new HashMap&lt;String, String&gt;(); }
+ *          for ( java.util.Map.Entry&lt;Long, Date&gt; entry : source.entrySet() ) } {
+ *              String key = new DecimalFormat( "" ).format( entry.getKey() );
+ *              String value = new SimpleDateFormat( "dd.MM.yyyy" ).format( entry.getValue() );
+ *              map.put( key, value );
+ *          }
+ *          // ...
+ *      }
+ * }
+ * </code></pre>
+ *
+ * <p><strong>NOTE:</strong> at least one element needs to be specified</p>
  *
  * @author Gunnar Morling
  */
@@ -28,8 +56,12 @@ public @interface MapMapping {
     /**
      * A format string as processable by {@link SimpleDateFormat} if the annotated method maps from a map with key type
      * {@code String} to an map with key type {@link Date} or vice-versa. Will be ignored for all other key types.
+     * <p>
+     * If the {@link #locale()} is specified, the format will consider the specified locale when processing the date.
+     * Otherwise, the system's default locale will be used.
      *
      * @return A date format string as processable by {@link SimpleDateFormat}.
+     * @see #locale()
      */
     String keyDateFormat() default "";
 
@@ -37,27 +69,50 @@ public @interface MapMapping {
      * A format string as processable by {@link SimpleDateFormat} if the annotated method maps from a map with value
      * type {@code String} to an map with value type {@link Date} or vice-versa. Will be ignored for all other value
      * types.
+     * <p>
+     * If the {@link #locale()} is specified, the format will consider the specified locale when processing the date.
+     * Otherwise, the system's default locale will be used.
      *
      * @return A date format string as processable by {@link SimpleDateFormat}.
+     * @see #locale()
      */
     String valueDateFormat() default "";
 
     /**
      * A format string as processable by {@link DecimalFormat} if the annotated method maps from a
      *  {@link Number} to a {@link String} or vice-versa. Will be ignored for all other key types.
+     * <p>
+     * If the {@link #locale()} is specified, the number format will be applied in the context of the given locale.
+     * Otherwise, the system's default locale will be used.
      *
      * @return A decimal format string as processable by {@link DecimalFormat}.
+     * @see #locale()
      */
     String keyNumberFormat() default "";
 
     /**
      * A format string as processable by {@link DecimalFormat} if the annotated method maps from a
      *  {@link Number} to a {@link String} or vice-versa. Will be ignored for all other value types.
+     * <p>
+     * If the {@link #locale()} is specified, the number format will be applied in the context of the given locale.
+     * Otherwise, the system's default locale will be used.
      *
      * @return A decimal format string as processable by {@link DecimalFormat}.
+     * @see #locale()
      */
     String valueNumberFormat() default "";
 
+    /**
+     * Specifies the locale to be used when processing {@link SimpleDateFormat} or {@link DecimalFormat} for key or
+     * value mappings in maps. The locale should be a plain tag representing the language, such as "en" for English,
+     * "de" for German, etc.
+     * <p>
+     * If no locale is specified, the system's default locale will be used.
+     *
+     * @return A string representing the locale to be used when formatting dates or numbers in maps.
+     */
+    String locale() default "";
+
     /**
      * A key value qualifier can be specified to aid the selection process of a suitable mapper. This is useful in
      * case multiple mappers (hand written of internal) qualify and result in an 'Ambiguous mapping methods found'
@@ -66,6 +121,7 @@ public @interface MapMapping {
      * A qualifier is a custom annotation and can be placed on either a hand written mapper class or a method.
      *
      * @return the qualifiers
+     * @see Qualifier
      */
     Class<? extends Annotation>[] keyQualifiedBy() default { };
 
@@ -93,6 +149,7 @@ public @interface MapMapping {
      * A qualifier is a custom annotation and can be placed on either a hand written mapper class or a method.
      *
      * @return the qualifiers
+     * @see Qualifier
      */
     Class<? extends Annotation>[] valueQualifiedBy() default { };
 
@@ -139,4 +196,32 @@ public @interface MapMapping {
      * @return The strategy to be applied when {@code null} is passed as source value to the methods of this mapping.
      */
     NullValueMappingStrategy nullValueMappingStrategy() default NullValueMappingStrategy.RETURN_NULL;
+
+    /**
+     * Allows detailed control over the key mapping process.
+     *
+     * @return the mapping control
+     *
+     * @since 1.4
+
+     * @see org.mapstruct.control.DeepClone
+     * @see org.mapstruct.control.NoComplexMapping
+     * @see org.mapstruct.control.MappingControl
+     */
+    Class<? extends Annotation> keyMappingControl() default MappingControl.class;
+
+
+    /**
+     * Allows detailed control over the value mapping process.
+     *
+     * @return the mapping control
+     *
+     * @since 1.4
+     *
+     * @see org.mapstruct.control.DeepClone
+     * @see org.mapstruct.control.NoComplexMapping
+     * @see org.mapstruct.control.MappingControl
+     */
+    Class<? extends Annotation> valueMappingControl() default MappingControl.class;
+
 }

core/src/main/java/org/mapstruct/Mapper.java

@@ -5,20 +5,76 @@
  */
 package org.mapstruct;
 
+import java.lang.annotation.Annotation;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
+import org.mapstruct.control.MappingControl;
 import org.mapstruct.factory.Mappers;
 
 import static org.mapstruct.NullValueCheckStrategy.ON_IMPLICIT_CONVERSION;
+import static org.mapstruct.SubclassExhaustiveStrategy.COMPILE_ERROR;
 
 /**
  * Marks an interface or abstract class as a mapper and activates the generation of a implementation of that type via
  * MapStruct.
  *
+ * <p>
+ * <strong>Example 1:</strong> Creating mapper
+ * </p>
+ * <pre><code class='java'>
+ * &#64;Mapper
+ * public interface CarMapper {
+ *     CarDto toCarDto(Car source);
+ * }
+ * </code></pre>
+ * <p>
+ * <strong>Example 2:</strong> Use additional mappers with parameters {@link #uses()}, {@link #componentModel()}
+ * and {@link #injectionStrategy()}
+ * </p>
+ * <pre><code class='java'>
+ * // we have MarkMapper (map field "mark" to field "name" to upper case)
+ * &#64;Mapper(componentModel = MappingConstants.ComponentModel.SPRING)
+ * public class MarkMapper {
+ *     public String mapMark(String mark) {
+ *         return mark.toUpperCase();
+ *     }
+ * }
+ * // we have CarMapper
+ * &#64;Mapper(
+ *      componentModel = MappingConstants.ComponentModel.SPRING,
+ *      uses = MarkMapper.class,
+ *      injectionStrategy = InjectionStrategy.CONSTRUCTOR)
+ * public interface CarMapper {
+ *     &#64;Mapping(target = "name", source = "mark")
+ *     CarDto convertMap(CarEntity carEntity);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * &#64;Component
+ * public class CarMapperImpl implements CarMapper {
+ *     private final MarkMapper markMapper;
+ *     &#64;Autowired
+ *     public CarMapperImpl(MarkMapper markMapper) {
+ *         this.markMapper = markMapper;
+ *     }
+ *     &#64;Override
+ *     public CarDto convertMap(CarEntity carEntity) {
+ *         if ( carEntity == null ) {
+ *             return null;
+ *         }
+ *         CarDto carDto = new CarDto();
+ *         carDto.setName( markMapper.mapMark( carEntity.getMark() ) );
+ *         return carDto;
+ *     }
+ * }
+ * </code></pre>
+ *
  * @author Gunnar Morling
+ * @see Javadoc
  */
 @Target(ElementType.TYPE)
 @Retention(RetentionPolicy.CLASS)
@@ -87,14 +143,19 @@ public @interface Mapper {
      * can be retrieved via {@code @Autowired}</li>
      * <li>
      * {@code jsr330}: the generated mapper is annotated with {@code @javax.inject.Named} and
-     * {@code @Singleton}, and can be retrieved via {@code @Inject}</li>
+     * {@code @Singleton}, and can be retrieved via {@code @Inject}.
+     * The annotations will either be from javax.inject or jakarta.inject,
+     * depending on which one is available, with javax.inject having precedence.</li>
+     * <li>
+     * {@code jakarta}: the generated mapper is annotated with {@code @jakarta.inject.Named} and
+     * {@code @Singleton}, and can be retrieved via {@code @Inject}.</li>
      * </ul>
-     * The method overrides an unmappedTargetPolicy set in a central configuration set
+     * The method overrides a componentModel set in a central configuration set
      * by {@link #config() }
      *
      * @return The component model for the generated mapper.
      */
-    String componentModel() default "default";
+    String componentModel() default MappingConstants.ComponentModel.DEFAULT;
 
     /**
      * Specifies the name of the implementation class. The {@code <CLASS_NAME>} will be replaced by the
@@ -148,6 +209,32 @@ public @interface Mapper {
      */
     NullValueMappingStrategy nullValueMappingStrategy() default NullValueMappingStrategy.RETURN_NULL;
 
+    /**
+     * The strategy to be applied when {@code null} is passed as source argument value to an {@link IterableMapping} of
+     * this mapper. If unset, the strategy set with {@link #nullValueMappingStrategy()} will be applied. If neither
+     * strategy is configured, the strategy given via {@link MapperConfig#nullValueIterableMappingStrategy()} will be
+     * applied, using {@link NullValueMappingStrategy#RETURN_NULL} by default.
+     *
+     * @since 1.5
+     *
+     * @return The strategy to be applied when {@code null} is passed as source value to an {@link IterableMapping} of
+     * this mapper.
+     */
+    NullValueMappingStrategy nullValueIterableMappingStrategy() default NullValueMappingStrategy.RETURN_NULL;
+
+    /**
+     * The strategy to be applied when {@code null} is passed as source argument value to a {@link MapMapping} of this
+     * mapper. If unset, the strategy set with {@link #nullValueMappingStrategy()} will be applied. If neither strategy
+     * is configured, the strategy given via {@link MapperConfig#nullValueMapMappingStrategy()} will be applied, using
+     * {@link NullValueMappingStrategy#RETURN_NULL} by default.
+     *
+     * @since 1.5
+     *
+     * @return The strategy to be applied when {@code null} is passed as source value to a {@link MapMapping} of this
+     * mapper.
+     */
+    NullValueMappingStrategy nullValueMapMappingStrategy() default NullValueMappingStrategy.RETURN_NULL;
+
     /**
      * The strategy to be applied when a source bean property is {@code null} or not present. If no strategy is
      * configured, the strategy given via {@link MapperConfig#nullValuePropertyMappingStrategy()} will be applied,
@@ -183,6 +270,29 @@ public @interface Mapper {
      */
     NullValueCheckStrategy nullValueCheckStrategy() default ON_IMPLICIT_CONVERSION;
 
+    /**
+     * Determines how to handle missing implementation for super classes when using the {@link SubclassMapping}.
+     *
+     * Can be overridden by the one on {@link BeanMapping}, but overrides {@link MapperConfig}.
+     *
+     * @return strategy to handle missing implementation combined with {@link SubclassMappings}.
+     *
+     * @since 1.5
+     */
+    SubclassExhaustiveStrategy subclassExhaustiveStrategy() default COMPILE_ERROR;
+
+    /**
+     * Specifies the exception type to be thrown when a missing subclass implementation is detected
+     * in combination with {@link SubclassMappings}, based on the {@link #subclassExhaustiveStrategy()}.
+     * <p>
+     * This exception will only be thrown when the {@code subclassExhaustiveStrategy} is set to
+     * {@link SubclassExhaustiveStrategy#RUNTIME_EXCEPTION}.
+     *
+     * @return the exception class to throw when missing implementations are found.
+     *         Defaults to {@link IllegalArgumentException}.
+     */
+    Class<? extends Exception> subclassExhaustiveException() default IllegalArgumentException.class;
+
     /**
      * Determines whether to use field or constructor injection. This is only used on annotated based component models
      * such as CDI, Spring and JSR 330.
@@ -201,7 +311,7 @@ public @interface Mapper {
      * Can be configured by the {@link MapperConfig#disableSubMappingMethodsGeneration()} as well.
      * <p>
      * Note: If you need to use {@code disableSubMappingMethodsGeneration} please contact the MapStruct team at
-     * <a href="http://mapstruct.org">mapstruct.org</a> or
+     * <a href="https://mapstruct.org">mapstruct.org</a> or
      * <a href="https://github.com/mapstruct/mapstruct">github.com/mapstruct/mapstruct</a> to share what problem you
      * are facing with the automatic sub-mapping generation.
      *
@@ -229,4 +339,53 @@ public @interface Mapper {
      * @since 1.3
      */
     Builder builder() default @Builder;
+
+    /**
+     * Allows detailed control over the mapping process.
+     *
+     * @return the mapping control
+     *
+     * @since 1.4
+     *
+     * @see org.mapstruct.control.DeepClone
+     * @see org.mapstruct.control.NoComplexMapping
+     * @see org.mapstruct.control.MappingControl
+     */
+    Class<? extends Annotation> mappingControl() default MappingControl.class;
+
+    /**
+     * Exception that should be thrown by the generated code if no mapping matches for enums.
+     * If no exception is configured, the exception given via {@link MapperConfig#unexpectedValueMappingException()}
+     * will be used, using {@link IllegalArgumentException} by default.
+     *
+     * <p>
+     * Note:
+     * <ul>
+     *     <li>
+     *      The defined exception should at least have a constructor with a {@link String} parameter.
+     *     </li>
+     *     <li>
+     *      If the defined exception is a checked exception then the enum mapping methods should have that exception
+     *      in the throws clause.
+     *     </li>
+     * </ul>
+     *
+     * @return the exception that should be used in the generated code
+     *
+     * @since 1.4
+     */
+    Class<? extends Exception> unexpectedValueMappingException() default IllegalArgumentException.class;
+
+    /**
+     * Flag indicating whether the addition of a time stamp in the {@code @Generated} annotation should be suppressed.
+     * i.e. not be added.
+     *
+     * The method overrides the flag set in a central configuration set by {@link #config()}
+     * or through an annotation processor option.
+     *
+     * @return whether the addition of a timestamp should be suppressed
+     *
+     * @since 1.5
+     */
+    boolean suppressTimestampInGenerated() default false;
 }

core/src/main/java/org/mapstruct/MapperConfig.java

@@ -5,14 +5,17 @@
  */
 package org.mapstruct;
 
+import java.lang.annotation.Annotation;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
+import org.mapstruct.control.MappingControl;
 import org.mapstruct.factory.Mappers;
 
 import static org.mapstruct.NullValueCheckStrategy.ON_IMPLICIT_CONVERSION;
+import static org.mapstruct.SubclassExhaustiveStrategy.COMPILE_ERROR;
 
 /**
  * Marks a class or interface as configuration source for generated mappers. This allows to share common configurations
@@ -30,6 +33,36 @@ import static org.mapstruct.NullValueCheckStrategy.ON_IMPLICIT_CONVERSION;
  * types are assignable.
  * </p>
  *
+ * <p>
+ * <strong>Example:</strong>
+ * </p>
+ * <pre><code class='java'>
+ * // create config
+ * &#64;MapperConfig(
+ *     uses = CustomMapperViaMapperConfig.class,
+ *     unmappedTargetPolicy = ReportingPolicy.ERROR
+ * )
+ * public interface CentralConfig {
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // use config
+ * &#64;Mapper(config = CentralConfig.class, uses = { CustomMapperViaMapper.class } )
+ * public interface SourceTargetMapper {
+ *   // ...
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // result after applying CentralConfig
+ * &#64;Mapper(
+ *     uses = { CustomMapperViaMapper.class, CustomMapperViaMapperConfig.class },
+ *     unmappedTargetPolicy = ReportingPolicy.ERROR
+ * )
+ * public interface SourceTargetMapper {
+ *    // ...
+ * }
+ * </code></pre>
+ *
  * @author Sjaak Derksen
  * @see Mapper#config()
  */
@@ -44,6 +77,18 @@ public @interface MapperConfig {
      */
     Class<?>[] uses() default { };
 
+    /**
+     * Additional types for which an import statement is to be added to the generated mapper implementation class.
+     * This allows to refer to those types from within mapping expressions given via {@link Mapping#expression()},
+     * {@link Mapping#defaultExpression()} or using
+     * their simple name rather than their fully-qualified name.
+     *
+     * @return classes to add in the imports of the generated implementation.
+     *
+     * @since 1.4
+     */
+    Class<?>[] imports() default { };
+
     /**
      * How unmapped properties of the source type of a mapping should be
      * reported.
@@ -86,12 +131,17 @@ public @interface MapperConfig {
      * can be retrieved via {@code @Autowired}</li>
      * <li>
      * {@code jsr330}: the generated mapper is annotated with {@code @javax.inject.Named} and
-     * {@code @Singleton}, and can be retrieved via {@code @Inject}</li>
+     * {@code @Singleton}, and can be retrieved via {@code @Inject}.
+     * The annotations will either be from javax.inject or jakarta.inject,
+     * depending on which one is available, with javax.inject having precedence.</li>
+     * <li>
+     * {@code jakarta}: the generated mapper is annotated with {@code @jakarta.inject.Named} and
+     * {@code @Singleton}, and can be retrieved via {@code @Inject}.</li>
      * </ul>
      *
      * @return The component model for the generated mapper.
      */
-    String componentModel() default "default";
+    String componentModel() default MappingConstants.ComponentModel.DEFAULT;
 
     /**
      * Specifies the name of the implementation class. The {@code <CLASS_NAME>} will be replaced by the
@@ -132,6 +182,28 @@ public @interface MapperConfig {
      */
     NullValueMappingStrategy nullValueMappingStrategy() default NullValueMappingStrategy.RETURN_NULL;
 
+    /**
+     * The strategy to be applied when {@code null} is passed as source argument value to an {@link IterableMapping}.
+     * If no strategy is configured, the strategy given via {@link #nullValueMappingStrategy()} will be applied, using
+     * {@link NullValueMappingStrategy#RETURN_NULL} by default.
+     *
+     * @since 1.5
+     *
+     * @return The strategy to be applied when {@code null} is passed as source value to an {@link IterableMapping}.
+     */
+    NullValueMappingStrategy nullValueIterableMappingStrategy() default NullValueMappingStrategy.RETURN_NULL;
+
+    /**
+     * The strategy to be applied when {@code null} is passed as source argument value to a {@link MapMapping}.
+     * If no strategy is configured, the strategy given via {@link #nullValueMappingStrategy()} will be applied, using
+     * {@link NullValueMappingStrategy#RETURN_NULL} by default.
+     *
+     * @since 1.5
+     *
+     * @return The strategy to be applied when {@code null} is passed as source value to a {@link MapMapping}.
+     */
+    NullValueMappingStrategy nullValueMapMappingStrategy() default NullValueMappingStrategy.RETURN_NULL;
+
     /**
      * The strategy to be applied when a source bean property is {@code null} or not present. If no strategy is
      * configured, {@link NullValuePropertyMappingStrategy#SET_TO_NULL} will be used by default.
@@ -166,6 +238,29 @@ public @interface MapperConfig {
      */
     NullValueCheckStrategy nullValueCheckStrategy() default ON_IMPLICIT_CONVERSION;
 
+    /**
+     * Determines how to handle missing implementation for super classes when using the {@link SubclassMapping}.
+     *
+     * Can be overridden by the one on {@link BeanMapping} or {@link Mapper}.
+     *
+     * @return strategy to handle missing implementation combined with {@link SubclassMappings}.
+     *
+     * @since 1.5
+     */
+    SubclassExhaustiveStrategy subclassExhaustiveStrategy() default COMPILE_ERROR;
+
+    /**
+     * Specifies the exception type to be thrown when a missing subclass implementation is detected
+     * in combination with {@link SubclassMappings}, based on the {@link #subclassExhaustiveStrategy()}.
+     * <p>
+     * This exception will only be thrown when the {@code subclassExhaustiveStrategy} is set to
+     * {@link SubclassExhaustiveStrategy#RUNTIME_EXCEPTION}.
+     *
+     * @return the exception class to throw when missing implementations are found.
+     *         Defaults to {@link IllegalArgumentException}.
+     */
+    Class<? extends Exception> subclassExhaustiveException() default IllegalArgumentException.class;
+
     /**
      * Determines whether to use field or constructor injection. This is only used on annotated based component models
      * such as CDI, Spring and JSR 330.
@@ -186,7 +281,7 @@ public @interface MapperConfig {
      * Can be overridden by {@link Mapper#disableSubMappingMethodsGeneration()}
      * <p>
      * Note: If you need to use {@code disableSubMappingMethodsGeneration} please contact the MapStruct team at
-     * <a href="http://mapstruct.org">mapstruct.org</a> or
+     * <a href="https://mapstruct.org">mapstruct.org</a> or
      * <a href="https://github.com/mapstruct/mapstruct">github.com/mapstruct/mapstruct</a> to share what problem you
      * are facing with the automatic sub-mapping generation.
      *
@@ -215,4 +310,52 @@ public @interface MapperConfig {
      * @since 1.3
      */
     Builder builder() default @Builder;
+
+    /**
+     * Allows detailed control over the mapping process.
+     *
+     * @return the mapping control
+     *
+     * @since 1.4
+     *
+     * @see org.mapstruct.control.DeepClone
+     * @see org.mapstruct.control.NoComplexMapping
+     * @see org.mapstruct.control.MappingControl
+     */
+    Class<? extends Annotation> mappingControl() default MappingControl.class;
+
+    /**
+     * Exception that should be thrown by the generated code if no mapping matches for enums.
+     * If no exception is configured, {@link IllegalArgumentException} will be used by default.
+     *
+     * <p>
+     * Note:
+     * <ul>
+     *     <li>
+     *      The defined exception should at least have a constructor with a {@link String} parameter.
+     *     </li>
+     *     <li>
+     *      If the defined exception is a checked exception then the enum mapping methods should have that exception
+     *      in the throws clause.
+     *     </li>
+     * </ul>
+     *
+     * @return the exception that should be used in the generated code
+     *
+     * @since 1.4
+     */
+    Class<? extends Exception> unexpectedValueMappingException() default IllegalArgumentException.class;
+
+    /**
+     * Flag indicating whether the addition of a time stamp in the {@code @Generated} annotation should be suppressed.
+     * i.e. not be added.
+     *
+     * The method overrides the flag set through an annotation processor option.
+     *
+     * @return whether the addition of a timestamp should be suppressed
+     *
+     * @since 1.5
+     */
+    boolean suppressTimestampInGenerated() default false;
 }
+

core/src/main/java/org/mapstruct/Mapping.java

@@ -15,27 +15,133 @@ import java.text.DecimalFormat;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 
+import org.mapstruct.control.MappingControl;
+
 import static org.mapstruct.NullValueCheckStrategy.ON_IMPLICIT_CONVERSION;
+
 /**
- * Configures the mapping of one bean attribute or enum constant.
+ * Configures the mapping of one bean attribute.
  * <p>
  * The name of the mapped attribute or constant is to be specified via {@link #target()}. For mapped bean attributes it
  * is assumed by default that the attribute has the same name in the source bean. Alternatively, one of
  * {@link #source()}, {@link #expression()} or {@link #constant()} can be specified to define the property source.
+ * </p>
  * <p>
  * In addition, the attributes {@link #dateFormat()} and {@link #qualifiedBy()} may be used to further define the
  * mapping.
+ * </p>
  *
  * <p>
- * <b>IMPORTANT NOTE:</b> the enum mapping capability is deprecated and replaced by {@link ValueMapping} it
- * will be removed in subsequent versions.
+ * <strong>Example 1:</strong> Implicitly mapping fields with the same name:
+ * </p>
+ * <pre><code class='java'>
+ * // Both classes HumanDto and Human have property with name "fullName"
+ * // properties with the same name will be mapped implicitly
+ * &#64;Mapper
+ * public interface HumanMapper {
+ *    HumanDto toHumanDto(Human human)
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates:
+ * &#64;Override
+ * public HumanDto toHumanDto(Human human) {
+ *    humanDto.setFullName( human.getFullName() );
+ *    // ...
+ * }
+ * </code></pre>
+ *
+ * <p><strong>Example 2:</strong> Mapping properties with different names</p>
+ * <pre><code class='java'>
+ * // We need map Human.companyName to HumanDto.company
+ * // we can use &#64;Mapping with parameters {@link #source()} and {@link #target()}
+ * &#64;Mapper
+ * public interface HumanMapper {
+ *    &#64;Mapping(source="companyName", target="company")
+ *    HumanDto toHumanDto(Human human)
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates:
+ * &#64;Override
+ * public HumanDto toHumanDto(Human human) {
+ *     humanDto.setCompany( human.getCompanyName() );
+ *      // ...
+ * }
+ * </code></pre>
+ * <p>
+ * <strong>Example 3:</strong> Mapping with expression
+ * <b>IMPORTANT NOTE:</b> Now it works only for Java
+ * </p>
+ * <pre><code class='java'>
+ * // We need map Human.name to HumanDto.countNameSymbols.
+ * // we can use {@link #expression()} for it
+ * &#64;Mapper
+ * public interface HumanMapper {
+ *    &#64;Mapping(target="countNameSymbols", expression="java(human.getName().length())")
+ *    HumanDto toHumanDto(Human human)
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates:
+ *&#64;Override
+ * public HumanDto toHumanDto(Human human) {
+ *    humanDto.setCountNameSymbols( human.getName().length() );
+ *    //...
+ * }
+ * </code></pre>
+ * <p>
+ * <strong>Example 4:</strong> Mapping to constant
+ * </p>
+ * <pre><code class='java'>
+ * // We need map HumanDto.name to string constant "Unknown"
+ * // we can use {@link #constant()} for it
+ * &#64;Mapper
+ * public interface HumanMapper {
+ *    &#64;Mapping(target="name", constant="Unknown")
+ *    HumanDto toHumanDto(Human human)
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * &#64;Override
+ * public HumanDto toHumanDto(Human human) {
+ *   humanDto.setName( "Unknown" );
+ *   // ...
+ * }
+ * </code></pre>
+ * <p>
+ * <strong>Example 5:</strong> Mapping with default value
+ * </p>
+ * <pre><code class='java'>
+ * // We need map Human.name to HumanDto.fullName, but if Human.name == null, then set value "Somebody"
+ * // we can use {@link #defaultValue()} or {@link #defaultExpression()} for it
+ * &#64;Mapper
+ * public interface HumanMapper {
+ *    &#64;Mapping(source="name", target="name", defaultValue="Somebody")
+ *    HumanDto toHumanDto(Human human)
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * &#64;Override
+ * public HumanDto toHumanDto(Human human) {
+ *    if ( human.getName() != null ) {
+ *       humanDto.setFullName( human.getName() );
+ *    }
+ *    else {
+ *       humanDto.setFullName( "Somebody" );
+ *    }
+ *   // ...
+ * }
+ * </code></pre>
  *
  * @author Gunnar Morling
  */
 
 @Repeatable(Mappings.class)
 @Retention(RetentionPolicy.CLASS)
-@Target(ElementType.METHOD)
+@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
 public @interface Mapping {
 
     /**
@@ -69,19 +175,38 @@ public @interface Mapping {
     /**
      * A format string as processable by {@link SimpleDateFormat} if the attribute is mapped from {@code String} to
      * {@link Date} or vice-versa. Will be ignored for all other attribute types and when mapping enum constants.
+     * <p>
+     * If the {@link #locale()} is also specified, the format will consider the specified locale when processing
+     * the date. Otherwise, the system's default locale will be used.
      *
      * @return A date format string as processable by {@link SimpleDateFormat}.
+     * @see #locale()
      */
     String dateFormat() default "";
 
     /**
      * A format string as processable by {@link DecimalFormat} if the annotated method maps from a
      *  {@link Number} to a {@link String} or vice-versa. Will be ignored for all other element types.
+     * <p>
+     * If the {@link #locale()} is also specified, the number format will be applied in the context of the given locale.
+     * Otherwise, the system's default locale will be used to process the number format.
      *
      * @return A decimal format string as processable by {@link DecimalFormat}.
+     * @see #locale()
      */
     String numberFormat() default "";
 
+    /**
+     * Specifies the locale to be used when processing {@link #dateFormat()} or {@link #numberFormat()}.
+     * <p>
+     * The locale should be a plain tag representing the language, such as "en" for English, "de" for German, etc.
+     * <p>
+     * If no locale is specified, the system's default locale will be used.
+     *
+     * @return A string representing the locale to be used when formatting dates or numbers.
+     */
+    String locale() default "";
+
     /**
      * A constant {@link String} based on which the specified target property is to be set.
      * <p>
@@ -109,6 +234,10 @@ public @interface Mapping {
      * </li>
      * </ol>
      * <p>
+     * You can use {@link #qualifiedBy()} or {@link #qualifiedByName()} to force the use of a conversion method
+     * even when one would not apply. (e.g. {@code String} to {@code String})
+     * </p>
+     * <p>
      * This attribute can not be used together with {@link #source()}, {@link #defaultValue()},
      * {@link #defaultExpression()} or {@link #expression()}.
      *
@@ -136,7 +265,7 @@ public @interface Mapping {
      * imported via {@link Mapper#imports()}.
      * <p>
      * This attribute can not be used together with {@link #source()}, {@link #defaultValue()},
-     * {@link #defaultExpression()} or {@link #constant()}.
+     * {@link #defaultExpression()}, {@link #qualifiedBy()}, {@link #qualifiedByName()} or {@link #constant()}.
      *
      * @return An expression specifying the value for the designated target property
      */
@@ -174,9 +303,12 @@ public @interface Mapping {
 
     /**
      * Whether the property specified via {@link #target()} should be ignored by the generated mapping method or not.
-     * This can be useful when certain attributes should not be propagated from source or target or when properties in
+     * This can be useful when certain attributes should not be propagated from source to target or when properties in
      * the target object are populated using a decorator and thus would be reported as unmapped target property by
      * default.
+     * <p>
+     * If you have multiple properties to ignore,
+     * you can use the {@link Ignored} annotation instead and group them all at once.
      *
      * @return {@code true} if the given property should be ignored, {@code false} otherwise
      */
@@ -186,8 +318,11 @@ public @interface Mapping {
      * A qualifier can be specified to aid the selection process of a suitable mapper. This is useful in case multiple
      * mapping methods (hand written or generated) qualify and thus would result in an 'Ambiguous mapping methods found'
      * error. A qualifier is a custom annotation and can be placed on a hand written mapper class or a method.
+     * <p>
+     * Note that {@link #defaultValue()} usage will also be converted using this qualifier.
      *
      * @return the qualifiers
+     * @see Qualifier
      */
     Class<? extends Annotation>[] qualifiedBy() default { };
 
@@ -199,6 +334,8 @@ public @interface Mapping {
      * Note that annotation-based qualifiers are generally preferable as they allow more easily to find references and
      * are safe for refactorings, but name-based qualifiers can be a less verbose alternative when requiring a large
      * number of qualifiers as no custom annotation types are needed.
+     * <p>
+     * Note that {@link #defaultValue()} usage will also be converted using this qualifier.
      *
      * @return One or more qualifier name(s)
      * @see #qualifiedBy()
@@ -206,6 +343,73 @@ public @interface Mapping {
      */
     String[] qualifiedByName() default { };
 
+    /**
+     * A qualifier can be specified to aid the selection process of a suitable presence check method.
+     * This is useful in case multiple presence check methods qualify and thus would result in an
+     * 'Ambiguous presence check methods found' error.
+     * A qualifier is a custom annotation and can be placed on a hand written mapper class or a method.
+     * This is similar to the {@link #qualifiedBy()}, but it is only applied for {@link Condition} methods.
+     *
+     * @return the qualifiers
+     * @see Qualifier
+     * @see #qualifiedBy()
+     * @since 1.5
+     */
+    Class<? extends Annotation>[] conditionQualifiedBy() default { };
+
+    /**
+     * String-based form of qualifiers for condition / presence check methods;
+     * When looking for a suitable presence check method for a given property, MapStruct will
+     * only consider those methods carrying directly or indirectly (i.e. on the class-level) a {@link Named} annotation
+     * for each of the specified qualifier names.
+     *
+     * This is similar like {@link #qualifiedByName()} but it is only applied for {@link Condition} methods.
+     * <p>
+     *   Note that annotation-based qualifiers are generally preferable as they allow more easily to find references and
+     *   are safe for refactorings, but name-based qualifiers can be a less verbose alternative when requiring a large
+     *   number of qualifiers as no custom annotation types are needed.
+     * </p>
+     *
+     *
+     * @return One or more qualifier name(s)
+     * @see #conditionQualifiedBy()
+     * @see #qualifiedByName()
+     * @see Named
+     * @since 1.5
+     */
+    String[] conditionQualifiedByName() default { };
+
+    /**
+     * A conditionExpression {@link String} based on which the specified property is to be checked
+     * whether it is present or not.
+     * <p>
+     * Currently, Java is the only supported "expression language" and expressions must be given in form of Java
+     * expressions using the following format: {@code java(<EXPRESSION>)}. For instance the mapping:
+     * <pre><code>
+     * &#64;Mapping(
+     *     target = "someProp",
+     *     conditionExpression = "java(s.getAge() &#60; 18)"
+     * )
+     * </code></pre>
+     * <p>
+     * will cause the following target property assignment to be generated:
+     * <pre><code>
+     *     if (s.getAge() &#60; 18) {
+     *         targetBean.setSomeProp( s.getSomeProp() );
+     *     }
+     * </code></pre>
+     * <p>
+     * Any types referenced in expressions must be given via their fully-qualified name. Alternatively, types can be
+     * imported via {@link Mapper#imports()}.
+     * <p>
+     * This attribute can not be used together with {@link #expression()} or {@link #constant()}.
+     *
+     * @return An expression specifying a condition check for the designated property
+     *
+     * @since 1.5
+     */
+    String conditionExpression() default "";
+
     /**
      * Specifies the result type of the mapping method to be used in case multiple mapping methods qualify.
      *
@@ -286,4 +490,17 @@ public @interface Mapping {
     NullValuePropertyMappingStrategy nullValuePropertyMappingStrategy()
         default NullValuePropertyMappingStrategy.SET_TO_NULL;
 
+    /**
+     * Allows detailed control over the mapping process.
+     *
+     * @return the mapping control
+     *
+     * @since 1.4
+     *
+     * @see org.mapstruct.control.DeepClone
+     * @see org.mapstruct.control.NoComplexMapping
+     * @see org.mapstruct.control.MappingControl
+     */
+    Class<? extends Annotation> mappingControl() default MappingControl.class;
+
 }

core/src/main/java/org/mapstruct/MappingConstants.java

@@ -23,12 +23,132 @@ public final class MappingConstants {
     /**
      * In an {@link ValueMapping} this represents any source that is not already mapped by either a defined mapping or
      * by means of name based mapping.
+     *
+     * NOTE: The value is only applicable to {@link ValueMapping#source()} and not to {@link ValueMapping#target()}.
      */
     public static final String ANY_REMAINING = "<ANY_REMAINING>";
 
     /**
      * In an {@link ValueMapping} this represents any source that is not already mapped by a defined mapping.
+     *
+     * NOTE: The value is only applicable to {@link ValueMapping#source()} and not to {@link ValueMapping#target()}.
+     *
      */
     public static final String ANY_UNMAPPED = "<ANY_UNMAPPED>";
 
+    /**
+     * In an {@link ValueMapping} this represents any target that will be mapped to an
+     * {@link java.lang.IllegalArgumentException} which will be thrown at runtime.
+     * <p>
+     * NOTE: The value is only applicable to {@link ValueMapping#target()} and not to {@link ValueMapping#source()}.
+     */
+    public static final String THROW_EXCEPTION = "<THROW_EXCEPTION>";
+
+    /**
+     * In an {@link EnumMapping} this represent the enum transformation strategy that adds a suffix to the source enum.
+     *
+     * @since 1.4
+     */
+    public static final String SUFFIX_TRANSFORMATION = "suffix";
+
+    /**
+     * In an {@link EnumMapping} this represent the enum transformation strategy that strips a suffix from the source
+     * enum.
+     *
+     * @since 1.4
+     */
+    public static final String STRIP_SUFFIX_TRANSFORMATION = "stripSuffix";
+
+    /**
+     * In an {@link EnumMapping} this represent the enum transformation strategy that adds a prefix to the source enum.
+     *
+     * @since 1.4
+     */
+    public static final String PREFIX_TRANSFORMATION = "prefix";
+
+    /**
+     * In an {@link EnumMapping} this represent the enum transformation strategy that strips a prefix from the source
+     * enum.
+     *
+     * @since 1.4
+     */
+    public static final String STRIP_PREFIX_TRANSFORMATION = "stripPrefix";
+
+    /**
+     * In an {@link EnumMapping} this represent the enum transformation strategy that applies case transformation
+     * at the source.
+     *
+     * @since 1.5
+     */
+    public static final String CASE_TRANSFORMATION = "case";
+
+    /**
+    * Specifies the component model constants to which the generated mapper should adhere.
+    * It can be used with the annotation {@link Mapper#componentModel()} or {@link MapperConfig#componentModel()}
+    *
+    * <p>
+    * <strong>Example:</strong>
+    * </p>
+    * <pre><code class='java'>
+    * // Spring component model
+    * &#64;Mapper(componentModel = MappingConstants.ComponentModel.SPRING)
+    * </code></pre>
+    *
+    * @since 1.5.0
+    */
+    public static final class ComponentModel {
+
+        private ComponentModel() {
+        }
+
+        /**
+         * The mapper uses no component model, instances are typically retrieved
+         * via {@link org.mapstruct.factory.Mappers#getMapper(java.lang.Class)}
+         *
+         */
+        public static final String DEFAULT = "default";
+
+        /**
+         * The generated mapper is an application-scoped CDI bean and can be retrieved via @Inject.
+         * The annotations are either from {@code javax} or {@code jakarta}.
+         * Priority have the {@code javax} annotations.
+         * In case you want to only use Jakarta then use {@link #JAKARTA_CDI}.
+         *
+         * @see #JAKARTA_CDI
+         */
+        public static final String CDI = "cdi";
+
+        /**
+         * The generated mapper is a Spring bean and can be retrieved via @Autowired
+         *
+         */
+        public static final String SPRING = "spring";
+
+        /**
+         * The generated mapper is annotated with @Named and @Singleton, and can be retrieved via @Inject.
+         * The annotations are either from {@code javax.inject} or {@code jakarta.inject}.
+         * Priority have the {@code javax.inject} annotations.
+         * In case you want to only use Jakarta then use {@link #JAKARTA}.
+         *
+         * @see #JAKARTA
+         */
+        public static final String JSR330 = "jsr330";
+
+        /**
+         * The generated mapper is annotated with @Named and @Singleton, and can be retrieved via @Inject.
+         * The annotations are from {@code jakarta.inject}.
+         * In case you want to use {@code javax.inject} then use {@link #JSR330}.
+         *
+         * @see #JSR330
+         */
+        public static final String JAKARTA = "jakarta";
+
+        /**
+         * The generated mapper is an application-scoped Jakarta CDI bean and can be retrieved via @Inject.
+         * @see #CDI
+         */
+        public static final String JAKARTA_CDI = "jakarta-cdi";
+
+    }
+
 }

core/src/main/java/org/mapstruct/MappingTarget.java

@@ -17,6 +17,43 @@ import java.lang.annotation.Target;
  * <p>
  * <b>NOTE:</b> The parameter passed as a mapping target <b>must</b> not be {@code null}.
  *
+ * <p>
+ * <strong>Example 1:</strong> Update exist bean without return value
+ * </p>
+ * <pre><code class='java'>
+ * &#64;Mapper
+ * public interface HumanMapper {
+ *     void updateHuman(HumanDto humanDto, @MappingTarget Human human);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * &#64;Override
+ * public void updateHuman(HumanDto humanDto, Human human) {
+ *     human.setName( humanDto.getName() );
+ *     // ...
+ * }
+ * </code></pre>
+ * <p>
+ * <strong>Example 2:</strong> Update exist bean and return it
+ * </p>
+ * <pre><code class='java'>
+ * &#64;Mapper
+ * public interface HumanMapper {
+ *     Human updateHuman(HumanDto humanDto, @MappingTarget Human human);
+ * }
+ * </code></pre>
+ * // generates:
+ * <pre><code class='java'>
+ * &#64;Override
+ * public Human updateHuman(HumanDto humanDto, Human human) {
+ *     // ...
+ *     human.setName( humanDto.getName() );
+ *     return human;
+ * }
+ *</code></pre>
+ *
+ *
  * @author Andreas Gudian
  */
 @Target(ElementType.PARAMETER)

core/src/main/java/org/mapstruct/Mappings.java

@@ -12,11 +12,37 @@ import java.lang.annotation.Target;
 
 /**
  * Configures the mappings of several bean attributes.
+ * <p>
+ * <strong>TIP: When using Java 8 or later, you can omit the @Mappings
+ * wrapper annotation and directly specify several @Mapping annotations on one method.</strong>
+ *
+ * <p>These two examples are equal.
+ * </p>
+ * <pre><code class='java'>
+ * // before Java 8
+ * &#64;Mapper
+ * public interface MyMapper {
+ *     &#64;Mappings({
+ *         &#64;Mapping(target = "firstProperty", source = "first"),
+ *         &#64;Mapping(target = "secondProperty", source = "second")
+ *     })
+ *     HumanDto toHumanDto(Human human);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // Java 8 and later
+ * &#64;Mapper
+ * public interface MyMapper {
+ *     &#64;Mapping(target = "firstProperty", source = "first"),
+ *     &#64;Mapping(target = "secondProperty", source = "second")
+ *     HumanDto toHumanDto(Human human);
+ * }
+ * </code></pre>
  *
  * @author Gunnar Morling
  */
 @Retention(RetentionPolicy.CLASS)
-@Target(ElementType.METHOD)
+@Target({ElementType.METHOD, ElementType.ANNOTATION_TYPE })
 public @interface Mappings {
 
     /**

core/src/main/java/org/mapstruct/Named.java

@@ -14,7 +14,7 @@ import java.lang.annotation.Target;
  * Marks mapping methods with the given qualifier name. Can be used to qualify a single method or all methods of a given
  * type by specifying this annotation on the type level.
  * <p>
- * Will be used to to select the correct mapping methods when mapping a bean property type, element of an iterable type
+ * Will be used to select the correct mapping methods when mapping a bean property type, element of an iterable type
  * or the key/value of a map type.
  * <p>
  * Example (both methods of {@code Titles} are capable to convert a string, but the ambiguity is resolved by applying

core/src/main/java/org/mapstruct/NullEnum.java

@@ -0,0 +1,15 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+/**
+ * To be used as a default value for enum class annotation elements.
+ *
+ * @author Ben Zegveld
+ * @since 1.6
+ */
+enum NullEnum {
+}

core/src/main/java/org/mapstruct/NullValueCheckStrategy.java

@@ -8,7 +8,7 @@ package org.mapstruct;
 /**
  * Strategy for dealing with null source values.
  *
- * <b>Note:</b> This strategy is not in effect when the a specific source presence check method is defined
+ * <b>Note:</b> This strategy is not in effect when a specific source presence check method is defined
  * in the service provider interface (SPI).
  *  <p>
  *  <b>Note</b>: some types of mappings (collections, maps), in which MapStruct is instructed to use a getter or adder

core/src/main/java/org/mapstruct/NullValuePropertyMappingStrategy.java

@@ -10,7 +10,7 @@ package org.mapstruct;
  * {@link NullValuePropertyMappingStrategy} can be defined on {@link MapperConfig}, {@link Mapper}, {@link BeanMapping}
  * and {@link Mapping}.
  * Precedence is arranged  in the reverse order. So {@link Mapping} will override {@link BeanMapping}, will
- * overide {@link Mapper}
+ * override {@link Mapper}
  *
  * The enum <b>only applies to update methods</b>: methods that update a pre-existing target (annotated with
  * {@code @}{@link MappingTarget}).

core/src/main/java/org/mapstruct/Qualifier.java

@@ -14,23 +14,70 @@ import java.lang.annotation.Target;
  * Declares an annotation type to be a qualifier. Qualifier annotations allow unambiguously identify a suitable mapping
  * method in case several methods qualify to map a bean property, iterable element etc.
  * <p>
- * For more info see:
+ * Can be used in:
  * <ul>
  * <li>{@link Mapping#qualifiedBy() }</li>
  * <li>{@link BeanMapping#qualifiedBy() }</li>
  * <li>{@link IterableMapping#qualifiedBy() }</li>
  * <li>{@link MapMapping#keyQualifiedBy() }</li>
  * <li>{@link MapMapping#valueQualifiedBy() }</li>
+ * <li>{@link SubclassMapping#qualifiedBy() }</li>
  * </ul>
- * Example:
+ * <p><strong>Example:</strong></p>
+ * <pre><code class='java'>
+ * // create qualifiers
+ * &#64;Qualifier
+ * &#64;Target(ElementType.TYPE)
+ * &#64;Retention(RetentionPolicy.CLASS)
+ * public &#64;interface TitleTranslator {}
  *
- * <pre>
  * &#64;Qualifier
  * &#64;Target(ElementType.METHOD)
  * &#64;Retention(RetentionPolicy.CLASS)
- * public &#64;interface EnglishToGerman {
+ * public @interface EnglishToGerman {}
+ *
+ * &#64;Qualifier
+ * &#64;Target(ElementType.METHOD)
+ * &#64;Retention(RetentionPolicy.CLASS)
+ * public @interface GermanToEnglish {}
+ * </code></pre>
+ * <pre><code class='java'>
+ * // we can create class with map methods
+ * &#64;TitleTranslator
+ * public class Titles {
+ *     &#64;EnglishToGerman
+ *     public String translateTitleEnglishToGerman(String title) {
+ *         // some mapping logic
+ *     }
+ *     &#64;GermanToEnglish
+ *     public String translateTitleGermanToEnglish(String title) {
+ *         // some mapping logic
+ *     }
  * }
- * </pre>
+ * </code></pre>
+ * <pre><code class='java'>
+ * // usage
+ * &#64;Mapper( uses = Titles.class )
+ * public interface MovieMapper {
+ *      &#64;Mapping( target = "title", qualifiedBy = { TitleTranslator.class, EnglishToGerman.class } )
+ *      GermanRelease toGerman( OriginalRelease movies );
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * public class MovieMapperImpl implements MovieMapper {
+ *      private final Titles titles = new Titles();
+ *      &#64;Override
+ *      public GermanRelease toGerman(OriginalRelease movies) {
+ *          if ( movies == null ) {
+ *              return null;
+ *          }
+ *          GermanRelease germanRelease = new GermanRelease();
+ *          germanRelease.setTitle( titles.translateTitleEnglishToGerman( movies.getTitle() ) );
+ *          return germanRelease;
+ *     }
+ * }
+ * </code></pre>
  *
  * <b>NOTE:</b> Qualifiers should have {@link RetentionPolicy#CLASS}.
  *

core/src/main/java/org/mapstruct/SourceParameterCondition.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * This annotation marks a method as a <em>check method</em> to check if a source parameter needs to be mapped.
+ * <p>
+ * By default, source parameters are checked against {@code null}, unless they are primitives.
+ * <p>
+ * Check methods have to return {@code boolean}.
+ * The following parameters are accepted for the presence check methods:
+ *     <ul>
+ *         <li>The mapping source parameter</li>
+ *         <li>{@code @}{@link Context} parameter</li>
+ *     </ul>
+ *
+ * <strong>Note:</strong> The usage of this annotation is <em>mandatory</em>
+ * for a method to be considered as a source check method.
+ *
+ * <pre><code class='java'>
+ * public class PresenceCheckUtils {
+ *
+ *   &#64;SourceParameterCondition
+ *   public static boolean isDefined(Car car) {
+ *      return car != null &#38;&#38; car.getId() != null;
+ *   }
+ * }
+ *
+ * &#64;Mapper(uses = PresenceCheckUtils.class)
+ * public interface CarMapper {
+ *
+ *     CarDto map(Car car);
+ * }
+ * </code></pre>
+ *
+ * The following implementation of {@code CarMapper} will be generated:
+ *
+ * <pre><code class='java'>
+ * public class CarMapperImpl implements CarMapper {
+ *
+ *     &#64;Override
+ *     public CarDto map(Car car) {
+ *         if ( !PresenceCheckUtils.isDefined( car ) ) {
+ *             return null;
+ *         }
+ *
+ *         CarDto carDto = new CarDto();
+ *
+ *         carDto.setId( car.getId() );
+ *         // ...
+ *
+ *         return carDto;
+ *     }
+ * }
+ * </code></pre>
+ *
+ * @author Filip Hrisafov
+ * @since 1.6
+ * @see Condition @Condition
+ */
+@Target({ ElementType.METHOD })
+@Retention(RetentionPolicy.CLASS)
+@Condition(appliesTo = ConditionStrategy.SOURCE_PARAMETERS)
+public @interface SourceParameterCondition {
+
+}

core/src/main/java/org/mapstruct/SourcePropertyName.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * This annotation marks a <em>presence check method</em> parameter as a source property name parameter.
+ * <p>
+ * This parameter enables conditional filtering based on source property name at run-time.
+ * Parameter must be of type {@link String} and can be present only in {@link Condition} method.
+ * </p>
+ *
+ * @author Oliver Erhart
+ * @since 1.6
+ */
+@Target(ElementType.PARAMETER)
+@Retention(RetentionPolicy.CLASS)
+public @interface SourcePropertyName {
+}

core/src/main/java/org/mapstruct/SubclassExhaustiveStrategy.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+/**
+ * Strategy for dealing with subclassMapping annotated methods.
+ *
+ * @since 1.5
+ * @author Ben Zegveld
+ */
+public enum SubclassExhaustiveStrategy {
+
+    /**
+     * If there is no valid constructor or known method to create the return value of a with `@SubclassMapping`
+     * annotated mapping then a compilation error will be thrown.
+     */
+    COMPILE_ERROR,
+
+    /**
+     * If there is no valid constructor or known method to create the return value of a with `@SubclassMapping`
+     * annotated mapping then an {@link IllegalArgumentException} will be thrown if a call is made with a type for which
+     * there is no {@link SubclassMapping} available.
+     */
+    RUNTIME_EXCEPTION;
+}

core/src/main/java/org/mapstruct/SubclassMapping.java

@@ -0,0 +1,110 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.Annotation;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Repeatable;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.mapstruct.util.Experimental;
+
+/**
+ * Configures the mapping to handle hierarchy of the source type.
+ * <p>
+ * The subclass to be mapped is to be specified via {@link #source()}.
+ * The subclass to map to is to be specified via {@link #target()}.
+ * </p>
+ * <p>
+ * This annotation can be combined with &#64;Mapping annotations.
+ * </p>
+ *
+ * <pre><code class='java'>
+ * &#64;Mapper
+ * public interface MyMapper {
+ *    &#64;SubclassMapping (target = TargetSubclass.class, source = SourceSubclass.class)
+ *    TargetParent mapParent(SourceParent parent);
+ *
+ *    TargetSubclass mapSubclass(SourceSubclass subInstant);
+ * }
+ * </code></pre>
+ * Below follow examples of the implementation for the mapParent method.
+ * <strong>Example 1:</strong> For parents that cannot be created. (e.g. abstract classes or interfaces)
+ * <pre><code class='java'>
+ * // generates
+ * &#64;Override
+ * public TargetParent mapParent(SourceParent parent) {
+ *     if (parent instanceof SourceSubclass) {
+ *         return mapSubclass( (SourceSubclass) parent );
+ *     }
+ *     else {
+ *         throw new IllegalArgumentException("Not all subclasses are supported for this mapping. Missing for "
+ *                    + parent.getClass());
+ *     }
+ * }
+ * </code></pre>
+ * <strong>Example 2:</strong> For parents that can be created. (e.g. normal classes or interfaces with
+ * &#64;Mapper( uses = ObjectFactory.class ) )
+ * <pre><code class='java'>
+ * // generates
+ * &#64;Override
+ * public TargetParent mapParent(SourceParent parent) {
+ *     TargetParent targetParent1;
+ *     if (parent instanceof SourceSubclass) {
+ *         targetParent1 = mapSubclass( (SourceSubclass) parent );
+ *     }
+ *     else {
+ *         targetParent1 = new TargetParent();
+ *         // ...
+ *     }
+ * }
+ * </code></pre>
+ *
+ * @author Ben Zegveld
+ * @since 1.5
+ */
+@Repeatable(value = SubclassMappings.class)
+@Retention(RetentionPolicy.CLASS)
+@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
+@Experimental
+public @interface SubclassMapping {
+    /**
+     * @return the source subclass to check for before using the default mapping as fallback.
+     */
+    Class<?> source();
+
+    /**
+     * @return the target subclass to map the source to.
+     */
+    Class<?> target();
+
+    /**
+     * A qualifier can be specified to aid the selection process of a suitable mapper. This is useful in case multiple
+     * mapping methods (hand written or generated) qualify and thus would result in an 'Ambiguous mapping methods found'
+     * error. A qualifier is a custom annotation and can be placed on a hand written mapper class or a method.
+     *
+     * @return the qualifiers
+     * @see Qualifier
+     */
+    Class<? extends Annotation>[] qualifiedBy() default {};
+
+    /**
+     * String-based form of qualifiers; When looking for a suitable mapping method for a given property, MapStruct will
+     * only consider those methods carrying directly or indirectly (i.e. on the class-level) a {@link Named} annotation
+     * for each of the specified qualifier names.
+     * <p>
+     * Note that annotation-based qualifiers are generally preferable as they allow more easily to find references and
+     * are safe for refactorings, but name-based qualifiers can be a less verbose alternative when requiring a large
+     * number of qualifiers as no custom annotation types are needed.
+     *
+     * @return One or more qualifier name(s)
+     * @see #qualifiedBy()
+     * @see Named
+     */
+    String[] qualifiedByName() default {};
+}

core/src/main/java/org/mapstruct/SubclassMappings.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.mapstruct.util.Experimental;
+
+/**
+ * Configures the SubclassMappings of several subclasses.
+ * <p>
+ * <strong>TIP: When using java 8 or later, you can omit the @SubclassMappings
+ * Wrapper annotation and directly specify several @SubclassMapping annotations
+ * on one method.</strong>
+ * </p>
+ * <p>These two examples are equal.
+ * </p>
+ * <pre><code class='java'>
+ * // before java 8
+ * &#64;Mapper
+ * public interface MyMapper {
+ *     &#64;SubclassMappings({
+ *         &#64;SubclassMapping(source = FirstSub.class, target = FirstTargetSub.class),
+ *         &#64;SubclassMapping(source = SecondSub.class, target = SecondTargetSub.class)
+ *     })
+ *     ParentTarget toParentTarget(Parent parent);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // java 8 and later
+ * &#64;Mapper
+ * public interface MyMapper {
+ *     &#64;SubclassMapping(source = First.class, target = FirstTargetSub.class),
+ *     &#64;SubclassMapping(source = SecondSub.class, target = SecondTargetSub.class)
+ *     ParentTarget toParentTarget(Parent parent);
+ * }
+ * </code></pre>
+ *
+ * @author Ben Zegveld
+ * @since 1.5
+ */
+@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
+@Retention(RetentionPolicy.CLASS)
+@Experimental
+public @interface SubclassMappings {
+
+    /**
+     * @return the subclassMappings to apply.
+     */
+    SubclassMapping[] value();
+
+}

core/src/main/java/org/mapstruct/TargetPropertyName.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * This annotation marks a <em>presence check method</em> parameter as a target property name parameter.
+ * <p>
+ * This parameter enables conditional filtering based on target property name at run-time.
+ * Parameter must be of type {@link String} and can be present only in {@link Condition} method.
+ * </p>
+ * @author Nikola Ivačič
+ * @since 1.6
+ */
+@Target(ElementType.PARAMETER)
+@Retention(RetentionPolicy.CLASS)
+public @interface TargetPropertyName {
+}

core/src/main/java/org/mapstruct/TargetType.java

@@ -16,6 +16,35 @@ import java.lang.annotation.Target;
  * Not more than one parameter can be declared as {@code TargetType} and that parameter needs to be of type
  * {@link Class} (may be parameterized), or a super-type of it.
  *
+ * <p>
+ * <strong>Example:</strong>
+ * </p>
+ * <pre><code class='java'>
+ * public class EntityFactory {
+ *    public &lt;T extends BaseEntity&gt; T createEntity(@TargetType Class&lt;T&gt; entityClass) {
+ *         return // ... custom factory logic
+ *    }
+ * }
+ * &#64;Mapper(uses = EntityFactory.class)
+ * public interface CarMapper {
+ *     CarEntity carDtoToCar(CarDto dto);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * // generates
+ * public class CarMapperImpl implements CarMapper {
+ *     private final EntityFactory entityFactory = new EntityFactory();
+ *     &#64;Override
+ *     public CarEntity carDtoToCar(CarDto dto) {
+ *         if ( dto == null ) {
+ *             return null;
+ *         }
+ *         CarEntity carEntity = entityFactory.createEntity( CarEntity.class );
+ *         return carEntity;
+ *     }
+ * }
+ * </code></pre>
+ *
  * @author Andreas Gudian
  */
 @Target(ElementType.PARAMETER)

core/src/main/java/org/mapstruct/ValueMapping.java

@@ -18,18 +18,16 @@ import java.lang.annotation.Target;
  * <ol>
  * <li>Enumeration to Enumeration</li>
  * </ol>
- * <p>
- * <B>Example 1:</B>
+ * <b>Example 1:</b>
  *
- * <pre>
- * <code>
- * public enum OrderType { RETAIL, B2B, EXTRA, STANDARD, NORMAL }
+ * <pre><code>
+ * public enum OrderType { RETAIL, B2B, C2C, EXTRA, STANDARD, NORMAL }
  *
  * public enum ExternalOrderType { RETAIL, B2B, SPECIAL, DEFAULT }
  *
- * &#64;ValueMapping(source = "EXTRA", target = "SPECIAL"),
- * &#64;ValueMapping(source = "STANDARD", target = "DEFAULT"),
- * &#64;ValueMapping(source = "NORMAL", target = "DEFAULT")
+ * &#64;ValueMapping(target = "SPECIAL", source = "EXTRA"),
+ * &#64;ValueMapping(target = "DEFAULT", source = "STANDARD"),
+ * &#64;ValueMapping(target = "DEFAULT", source = "NORMAL")
  * ExternalOrderType orderTypeToExternalOrderType(OrderType orderType);
  * </code>
  * Mapping result:
@@ -45,13 +43,9 @@ import java.lang.annotation.Target;
  * +---------------------+----------------------------+
  * </pre>
  *
- * MapStruct will <B>WARN</B> on incomplete mappings. However, if for some reason no match is found an
- * {@link java.lang.IllegalStateException} will be thrown.
- * <p>
- * <B>Example 2:</B>
+ * <b>Example 2:</b>
  *
- * <pre>
- * <code>
+ * <pre><code>
  * &#64;ValueMapping( source = MappingConstants.NULL, target = "DEFAULT" ),
  * &#64;ValueMapping( source = "STANDARD", target = MappingConstants.NULL ),
  * &#64;ValueMapping( source = MappingConstants.ANY_REMAINING, target = "SPECIAL" )
@@ -70,11 +64,27 @@ import java.lang.annotation.Target;
  * +---------------------+----------------------------+
  * </pre>
  *
+ * <b>Example 3:</b>
+ *
+ * MapStruct will <B>WARN</B> on incomplete mappings. However, if for some reason no match is found, an
+ * {@link java.lang.IllegalStateException} will be thrown. This compile-time error can be avoided by
+ * using {@link MappingConstants#THROW_EXCEPTION} for {@link ValueMapping#target()}. It will result an
+ * {@link java.lang.IllegalArgumentException} at runtime.
+ * <pre><code>
+ * &#64;ValueMapping( source = "STANDARD", target = "DEFAULT" ),
+ * &#64;ValueMapping( source = "C2C", target = MappingConstants.THROW_EXCEPTION )
+ * ExternalOrderType orderTypeToExternalOrderType(OrderType orderType);
+ * </code>
+ * Mapping result:
+ * {@link java.lang.IllegalArgumentException} with the error message:
+ * Unexpected enum constant: C2C
+ * </pre>
+ *
  * @author Sjaak Derksen
  */
 @Repeatable(ValueMappings.class)
 @Retention(RetentionPolicy.CLASS)
-@Target(ElementType.METHOD)
+@Target({ElementType.METHOD, ElementType.ANNOTATION_TYPE})
 public @interface ValueMapping {
     /**
      * The source value constant to use for this mapping.
@@ -104,6 +114,7 @@ public @interface ValueMapping {
      * <ol>
      * <li>enum constant name</li>
      * <li>{@link MappingConstants#NULL}</li>
+     * <li>{@link MappingConstants#THROW_EXCEPTION}</li>
      * </ol>
      *
      * @return The target value.

core/src/main/java/org/mapstruct/ValueMappings.java

@@ -12,10 +12,35 @@ import java.lang.annotation.Target;
 
 /**
  * Constructs a set of value (constant) mappings.
+ * <p>
+ * <strong>TIP: When using Java 8 or later, you can omit the @ValueMappings
+ * wrapper annotation and directly specify several @ValueMapping annotations on one method.</strong>
+ *
+ * <p>These two examples are equal</p>
+ * <pre><code class='java'>
+ * // before Java 8
+ * &#64;Mapper
+ * public interface GenderMapper {
+ *     &#64;ValueMappings({
+ *         &#64;ValueMapping(target = "M", source = "MALE"),
+ *         &#64;ValueMapping(target = "F", source = "FEMALE")
+ *     })
+ *     GenderDto mapToDto(Gender gender);
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * //Java 8 and later
+ * &#64;Mapper
+ * public interface GenderMapper {
+ *     &#64;ValueMapping(target = "M", source = "MALE"),
+ *     &#64;ValueMapping(target = "F", source = "FEMALE")
+ *     GenderDto mapToDto(Gender gender);
+ * }
+ * </code></pre>
  *
  * @author Sjaak Derksen
  */
-@Target(ElementType.METHOD)
+@Target({ElementType.METHOD, ElementType.ANNOTATION_TYPE})
 @Retention(RetentionPolicy.CLASS)
 public @interface ValueMappings {
 

core/src/main/java/org/mapstruct/control/DeepClone.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.control;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import org.mapstruct.util.Experimental;
+
+/**
+ * Clones a source type to a target type (assuming source and target are of the same type).
+ *
+ * @author Sjaak Derksen
+ *
+ * @since 1.4
+ */
+@Retention(RetentionPolicy.CLASS)
+@Experimental
+@MappingControl( MappingControl.Use.MAPPING_METHOD )
+public @interface DeepClone {
+}

core/src/main/java/org/mapstruct/control/MappingControl.java

@@ -0,0 +1,152 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.control;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Repeatable;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+
+/**
+ * Controls which means of mapping are considered between the source and the target in mappings.
+ *
+ * <p>
+ * There are several applications of <code>MappingControl</code> conceivable. One application, "deep cloning" is
+ * explained below in the example.
+ * </p>
+ *
+ * <p>
+ * Another application is controlling so called "complex mappings", which are not always desirable and sometimes lead to
+ * unexpected behaviour and prolonged compilation time.
+ * </p>
+ *
+ * <p><strong>Example:</strong>Cloning of an object</p>
+ * <p>
+ * When all methods are allowed, MapStruct would make a shallow copy. It would take the <code>ShelveDTO</code> in
+ * the <code>FridgeDTO</code> and directly enter that as target on the target <code>FridgeDTO</code>. By disabling all
+ * other kinds of mappings apart from {@link MappingControl.Use#MAPPING_METHOD}, see {@link DeepClone} MapStruct is
+ * forced to generate mapping methods all through the object graph `FridgeDTO` and hence create a deep clone.
+ * </p>
+ * <pre><code class='java'>
+ * public class FridgeDTO {
+ *
+ *     private ShelveDTO shelve;
+ *
+ *     public ShelveDTO getShelve() {
+ *         return shelve;
+ *     }
+ *
+ *     public void setShelve(ShelveDTO shelve) {
+ *         this.shelve = shelve;
+ *     }
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * public class ShelveDTO {
+ *
+ *     private CoolBeerDTO coolBeer;
+ *
+ *     public CoolBeerDTO getCoolBeer() {
+ *         return coolBeer;
+ *     }
+ *
+ *     public void setCoolBeer(CoolBeerDTO coolBeer) {
+ *         this.coolBeer = coolBeer;
+ *     }
+ * }
+ * </code></pre>
+ * <pre><code class='java'>
+ * public class CoolBeerDTO {
+ *
+ *     private String beerCount;
+ *
+ *     public String getBeerCount() {
+ *         return beerCount;
+ *     }
+ *
+ *     public void setBeerCount(String beerCount) {
+ *         this.beerCount = beerCount;
+ *     }
+ * }
+ * </code></pre>
+ *
+ * <pre><code class='java'>
+ * &#64;Mapper(mappingControl = DeepClone.class)
+ * public interface CloningMapper {
+ *
+ *     CloningMapper INSTANCE = Mappers.getMapper( CloningMapper.class );
+ *
+ *     FridgeDTO clone(FridgeDTO in);
+ *
+ * }
+ * </code></pre>
+ *
+ * @author Sjaak Derksen
+ *
+ * @since 1.4
+ */
+@Retention(RetentionPolicy.CLASS)
+@Repeatable(MappingControls.class)
+@Target( ElementType.ANNOTATION_TYPE )
+@MappingControl( MappingControl.Use.DIRECT )
+@MappingControl( MappingControl.Use.BUILT_IN_CONVERSION )
+@MappingControl( MappingControl.Use.MAPPING_METHOD )
+@MappingControl( MappingControl.Use.COMPLEX_MAPPING )
+public @interface MappingControl {
+
+    Use value();
+
+    enum Use {
+
+        /**
+         * Controls the mapping, allows for type conversion from source type to target type
+         * <p>
+         * Type conversions are typically supported directly in Java. The "toString()" is such an example,
+         * which allows for mapping for instance a  {@link java.lang.Number} type to a {@link java.lang.String}.
+         * <p>
+         * Please refer to the MapStruct guide for more info.
+         *
+         * @since 1.4
+         */
+        BUILT_IN_CONVERSION,
+
+        /**
+         * Controls the mapping from source to target type, allows mapping by calling:
+         * <ol>
+         * <li>A type conversion, passed into a mapping method</li>
+         * <li>A mapping method, passed into a type conversion</li>
+         * <li>A mapping method passed into another mapping method</li>
+         * </ol>
+         *
+         * @since 1.4
+         */
+        COMPLEX_MAPPING,
+        /**
+         * Controls the mapping, allows for a direct mapping from source type to target type.
+         * <p>
+         * This means if source type and target type are of the same type, MapStruct will not perform
+         * any mappings anymore and assign the target to the source direct.
+         * <p>
+         * An exception are types from the package {@code java}, which will be mapped always directly.
+         *
+         * @since 1.4
+         */
+        DIRECT,
+
+        /**
+         * Controls the mapping, allows for Direct Mapping from source type to target type.
+         * <p>
+         * The mapping method can be either a custom referred mapping method, or a MapStruct built in
+         * mapping method.
+         *
+         * @since 1.4
+         */
+        MAPPING_METHOD
+    }
+
+}

core/src/main/java/org/mapstruct/control/MappingControls.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.control;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Allows multiple {@link MappingControl} on a class declaration.
+ *
+ * @author Sjaak Derksen
+ *
+ * @since 1.4
+ */
+@Retention(RetentionPolicy.CLASS)
+@Target(ElementType.ANNOTATION_TYPE)
+public @interface MappingControls {
+
+    MappingControl[] value();
+}

core/src/main/java/org/mapstruct/control/NoComplexMapping.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.control;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import org.mapstruct.util.Experimental;
+
+/**
+ * Disables complex mappings, mappings that require 2 mapping means (method, built-in conversion) to constitute
+ * a mapping from source to target.
+ *
+ * @see MappingControl.Use#COMPLEX_MAPPING
+ *
+ * @author Sjaak Derksen
+ *
+ * @since 1.4
+ */
+@Retention(RetentionPolicy.CLASS)
+@Experimental
+@MappingControl( MappingControl.Use.DIRECT )
+@MappingControl( MappingControl.Use.BUILT_IN_CONVERSION )
+@MappingControl( MappingControl.Use.MAPPING_METHOD )
+public @interface NoComplexMapping {
+}

core/src/main/java/org/mapstruct/package-info.java

@@ -13,6 +13,6 @@
  * This package contains several annotations which allow to configure how mapper interfaces are generated.
  * </p>
  *
- * @see <a href="http://mapstruct.org/">MapStruct reference documentation</a>
+ * @see <a href="https://mapstruct.org/">MapStruct reference documentation</a>
  */
 package org.mapstruct;

core/src/test/java/org/mapstruct/factory/MappersTest.java

@@ -7,7 +7,7 @@ package org.mapstruct.factory;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.mapstruct.test.model.Foo;
 import org.mapstruct.test.model.SomeClass;
 

distribution/pom.xml

@@ -12,7 +12,7 @@
     <parent>
         <groupId>org.mapstruct</groupId>
         <artifactId>mapstruct-parent</artifactId>
-        <version>1.4.0-SNAPSHOT</version>
+        <version>1.7.0-SNAPSHOT</version>
         <relativePath>../parent/pom.xml</relativePath>
     </parent>
 
@@ -34,6 +34,18 @@
             <groupId>org.freemarker</groupId>
             <artifactId>freemarker</artifactId>
         </dependency>
+        <!-- Needed here so references to MapStruct Gem classes can be resolved during JavaDoc generation -->
+        <dependency>
+            <groupId>org.mapstruct.tools.gem</groupId>
+            <artifactId>gem-api</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>jakarta.xml.bind</groupId>
+            <artifactId>jakarta.xml.bind-api</artifactId>
+            <scope>provided</scope>
+            <optional>true</optional>
+        </dependency>
     </dependencies>
 
     <build>
@@ -54,7 +66,7 @@
                                     <groupId>org.freemarker</groupId>
                                     <artifactId>freemarker</artifactId>
                                     <outputDirectory>${project.build.directory}/freemarker-unpacked</outputDirectory>
-                                    <includes>META-INF/LICENSE.txt,META-INF/NOTICE.txt</includes>
+                                    <includes>META-INF/LICENSE</includes>
                                 </artifactItem>
                             </artifactItems>
                         </configuration>
@@ -88,7 +100,7 @@
                     <doctitle>MapStruct ${project.version}</doctitle>
                     <windowtitle>MapStruct ${project.version}</windowtitle>
                     <bottom>
-                        <![CDATA[Copyright &copy; ${project.inceptionYear}-{currentYear} <a href="http://mapstruct.org/">MapStruct Authors</a>; All rights reserved. Released under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache Software License 2.0</a>.]]>
+                        <![CDATA[Copyright &copy; ${project.inceptionYear}-{currentYear} <a href="https://mapstruct.org/">MapStruct Authors</a>; All rights reserved. Released under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache Software License 2.0</a>.]]>
                     </bottom>
 
                     <groups>
@@ -96,18 +108,16 @@
                             <title>MapStruct API</title>
                             <packages>org.mapstruct*</packages>
                         </group>
+                        <group>
+                            <title>MapStruct Processor SPI</title>
+                            <packages>org.mapstruct.ap.spi*</packages>
+                        </group>
                         <group>
                             <title>MapStruct Processor</title>
                             <packages>org.mapstruct.ap*</packages>
                         </group>
                     </groups>
 
-                    <doclet>org.jboss.apiviz.APIviz</doclet>
-                    <docletArtifact>
-                        <groupId>org.jboss.apiviz</groupId>
-                        <artifactId>apiviz</artifactId>
-                        <version>1.3.2.GA</version>
-                    </docletArtifact>
                     <useStandardDocletOptions>true</useStandardDocletOptions>
                     <charset>UTF-8</charset>
                     <encoding>UTF-8</encoding>
@@ -116,6 +126,23 @@
                     <version>true</version>
                     <author>true</author>
                     <keywords>true</keywords>
+
+                    <!--
+                        There is a bug in JDK 11 (https://bugs.openjdk.java.net/browse/JDK-8215291) which doesn't work correctly when searching and adds undefined.
+                        It has been fixed since JDK 12, but not yet backported to JDK 11 (https://bugs.openjdk.java.net/browse/JDK-8244171).
+                        One workaround is https://stackoverflow.com/a/57284322/1115491.
+                         -->
+                    <bottom>
+                        <![CDATA[
+                            <script>
+                            if (typeof useModuleDirectories !== 'undefined') {
+                              useModuleDirectories = false;
+                            }
+                            </script>
+                        ]]>
+                    </bottom>
+                    <additionalJOption>--allow-script-in-comments</additionalJOption>
+
                 </configuration>
                 <executions>
                     <execution>
@@ -135,7 +162,7 @@
                         <descriptor>${basedir}/src/main/assembly/dist.xml</descriptor>
                     </descriptors>
                     <finalName>mapstruct-${project.version}</finalName>
-                    <tarLongFileMode>gnu</tarLongFileMode>
+                    <tarLongFileMode>posix</tarLongFileMode>
                 </configuration>
                 <executions>
                     <execution>
@@ -156,4 +183,21 @@
             </plugin>
         </plugins>
     </build>
+
+    <profiles>
+        <profile>
+            <id>jdk-11-or-newer</id>
+            <activation>
+                <jdk>[11</jdk>
+            </activation>
+            <dependencies>
+                <dependency>
+                    <groupId>javax.xml.bind</groupId>
+                    <artifactId>jaxb-api</artifactId>
+                    <scope>provided</scope>
+                    <optional>true</optional>
+                </dependency>
+            </dependencies>
+        </profile>
+    </profiles>
 </project>

distribution/src/main/assembly/dist.xml

@@ -42,11 +42,7 @@
             <outputDirectory>/</outputDirectory>
         </file>
         <file>
-            <source>target/freemarker-unpacked/META-INF/NOTICE.txt</source>
-            <outputDirectory>/</outputDirectory>
-        </file>
-        <file>
-            <source>target/freemarker-unpacked/META-INF/LICENSE.txt</source>
+            <source>target/freemarker-unpacked/META-INF/LICENSE</source>
             <outputDirectory>etc/freemarker</outputDirectory>
         </file>
         <file>

documentation/pom.xml

@@ -12,7 +12,7 @@
     <parent>
         <groupId>org.mapstruct</groupId>
         <artifactId>mapstruct-parent</artifactId>
-        <version>1.4.0-SNAPSHOT</version>
+        <version>1.7.0-SNAPSHOT</version>
         <relativePath>../parent/pom.xml</relativePath>
     </parent>
 
@@ -21,9 +21,9 @@
     <name>MapStruct Documentation</name>
 
     <properties>
-        <asciidoctorj.pdf.version>1.5.0-alpha.11</asciidoctorj.pdf.version>
-        <asciidoctorj.version>1.5.4</asciidoctorj.version>
-        <jruby.version>1.7.21</jruby.version>
+        <asciidoctorj.pdf.version>1.6.0</asciidoctorj.pdf.version>
+        <asciidoctorj.version>2.5.1</asciidoctorj.version>
+        <jruby.version>9.2.17.0</jruby.version>
     </properties>
     <dependencies>
     </dependencies>
@@ -33,7 +33,7 @@
             <plugin>
               <groupId>org.asciidoctor</groupId>
               <artifactId>asciidoctor-maven-plugin</artifactId>
-              <version>1.5.3</version>
+              <version>2.1.0</version>
               <dependencies>
                   <dependency>
                       <groupId>org.asciidoctor</groupId>
@@ -52,7 +52,6 @@
                   </dependency>
               </dependencies>
               <configuration>
-                    <sourceHighlighter>coderay</sourceHighlighter>
                     <sourceDocumentName>mapstruct-reference-guide.asciidoc</sourceDocumentName>
                     <attributes>
                         <mapstructVersion>${project.version}</mapstructVersion>

documentation/src/main/asciidoc/chapter-1-introduction.asciidoc

@@ -0,0 +1,16 @@
+[[introduction]]
+== Introduction
+
+MapStruct is a Java http://docs.oracle.com/javase/6/docs/technotes/guides/apt/index.html[annotation processor] for the generation of type-safe bean mapping classes.
+
+All you have to do is to define a mapper interface which declares any required mapping methods. During compilation, MapStruct will generate an implementation of this interface. This implementation uses plain Java method invocations for mapping between source and target objects, i.e. no reflection or similar.
+
+Compared to writing mapping code from hand, MapStruct saves time by generating code which is tedious and error-prone to write. Following a convention over configuration approach, MapStruct uses sensible defaults but steps out of your way when it comes to configuring or implementing special behavior.
+
+Compared to dynamic mapping frameworks, MapStruct offers the following advantages:
+
+* Fast execution by using plain method invocations instead of reflection
+* Compile-time type safety: Only objects and attributes mapping to each other can be mapped, no accidental mapping of an order entity into a customer DTO etc.
+* Clear error-reports at build time, if
+** mappings are incomplete (not all target properties are mapped)
+** mappings are incorrect (cannot find a proper mapping method or type conversion)

documentation/src/main/asciidoc/chapter-10-advanced-mapping-options.asciidoc

@@ -0,0 +1,608 @@
+== Advanced mapping options
+This chapter describes several advanced options which allow to fine-tune the behavior of the generated mapping code as needed.
+
+[[default-values-and-constants]]
+=== Default values and constants
+
+Default values can be specified to set a predefined value to a target property if the corresponding source property is `null`. Constants can be specified to set such a predefined value in any case. Default values and constants are specified as String values. When the target type is a primitive or a boxed type, the String value is taken literal. Bit / octal / decimal / hex patterns are allowed in such a case as long as they are a valid literal.
+In all other cases, constant or default values are subject to type conversion either via built-in conversions or the invocation of other mapping methods in order to match the type required by the target property.
+
+A mapping with a constant must not include a reference to a source property. The following example shows some mappings using default values and constants:
+
+.Mapping method with default values and constants
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper(uses = StringListMapper.class)
+public interface SourceTargetMapper {
+
+    SourceTargetMapper INSTANCE = Mappers.getMapper( SourceTargetMapper.class );
+
+    @Mapping(target = "stringProperty", source = "stringProp", defaultValue = "undefined")
+    @Mapping(target = "longProperty", source = "longProp", defaultValue = "-1")
+    @Mapping(target = "stringConstant", constant = "Constant Value")
+    @Mapping(target = "integerConstant", constant = "14")
+    @Mapping(target = "longWrapperConstant", constant = "3001")
+    @Mapping(target = "dateConstant", dateFormat = "dd-MM-yyyy", constant = "09-01-2014")
+    @Mapping(target = "stringListConstants", constant = "jack-jill-tom")
+    Target sourceToTarget(Source s);
+}
+----
+====
+
+If `s.getStringProp() == null`, then the target property `stringProperty` will be set to `"undefined"` instead of applying the value from `s.getStringProp()`. If `s.getLongProperty() == null`, then the target property `longProperty` will be set to `-1`.
+The String `"Constant Value"` is set as is to the target property `stringConstant`. The value `"3001"` is type-converted to the `Long` (wrapper) class of target property `longWrapperConstant`. Date properties also require a date format. The constant `"jack-jill-tom"` demonstrates how the hand-written class `StringListMapper` is invoked to map the dash-separated list into a `List<String>`.
+
+[[expressions]]
+=== Expressions
+
+By means of Expressions it will be possible to include constructs from a number of languages.
+
+Currently only Java is supported as a language. This feature is e.g. useful to invoke constructors. The entire source object is available for usage in the expression. Care should be taken to insert only valid Java code: MapStruct will not validate the expression at generation-time, but errors will show up in the generated classes during compilation.
+
+The example below demonstrates how two source properties can be mapped to one target:
+
+.Mapping method using an expression
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface SourceTargetMapper {
+
+    SourceTargetMapper INSTANCE = Mappers.getMapper( SourceTargetMapper.class );
+
+    @Mapping(target = "timeAndFormat",
+         expression = "java( new org.sample.TimeAndFormat( s.getTime(), s.getFormat() ) )")
+    Target sourceToTarget(Source s);
+}
+----
+====
+
+The example demonstrates how the source properties `time` and `format` are composed into one target property `TimeAndFormat`. Please note that the fully qualified package name is specified because MapStruct does not take care of the import of the `TimeAndFormat` class (unless it's used otherwise explicitly in the `SourceTargetMapper`). This can be resolved by defining `imports` on the `@Mapper` annotation.
+
+.Declaring an import
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+imports org.sample.TimeAndFormat;
+
+@Mapper( imports = TimeAndFormat.class )
+public interface SourceTargetMapper {
+
+    SourceTargetMapper INSTANCE = Mappers.getMapper( SourceTargetMapper.class );
+
+    @Mapping(target = "timeAndFormat",
+         expression = "java( new TimeAndFormat( s.getTime(), s.getFormat() ) )")
+    Target sourceToTarget(Source s);
+}
+----
+====
+
+[[default-expressions]]
+=== Default Expressions
+
+Default expressions are a combination of default values and expressions. They will only be used when the source attribute is `null`.
+
+The same warnings and restrictions apply to default expressions that apply to expressions. Only Java is supported, and MapStruct will not validate the expression at generation-time.
+
+The example below demonstrates how a default expression can be used to set a value when the source attribute is not present (e.g. is `null`):
+
+.Mapping method using a default expression
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+imports java.util.UUID;
+
+@Mapper( imports = UUID.class )
+public interface SourceTargetMapper {
+
+    SourceTargetMapper INSTANCE = Mappers.getMapper( SourceTargetMapper.class );
+
+    @Mapping(target="id", source="sourceId", defaultExpression = "java( UUID.randomUUID().toString() )")
+    Target sourceToTarget(Source s);
+}
+----
+====
+
+The example demonstrates how to use defaultExpression to set an `ID` field if the source field is null, this could be used to take the existing `sourceId` from the source object if it is set, or create a new `Id` if it isn't. Please note that the fully qualified package name is specified because MapStruct does not take care of the import of the `UUID` class (unless it’s used otherwise explicitly in the `SourceTargetMapper`). This can be resolved by defining imports on the @Mapper annotation (see <<expressions>>).
+
+[[sub-class-mappings]]
+=== Subclass Mapping
+
+When both input and result types have an inheritance relation, you would want the correct specialization be mapped to the matching specialization.
+Suppose an `Apple` and a `Banana`, which are both specializations of `Fruit`.
+
+.Specifying the sub class mappings of a fruit mapping
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface FruitMapper {
+
+    @SubclassMapping( source = AppleDto.class, target = Apple.class )
+    @SubclassMapping( source = BananaDto.class, target = Banana.class )
+    Fruit map( FruitDto source );
+
+}
+----
+====
+
+If you would just use a normal mapping both the `AppleDto` and the `BananaDto` would be made into a `Fruit` object, instead of an `Apple` and a `Banana` object.
+By using the subclass mapping an `AppleDtoToApple` mapping will be used for `AppleDto` objects, and an `BananaDtoToBanana` mapping will be used for `BananaDto` objects.
+If you try to map a `GrapeDto` it would still turn it into a `Fruit`.
+
+In the case that the `Fruit` is an abstract class or an interface, you would get a compile error.
+
+To allow mappings for abstract classes or interfaces you need to set the `subclassExhaustiveStrategy` to `RUNTIME_EXCEPTION`, you can do this at the `@MapperConfig`, `@Mapper` or `@BeanMapping` annotations. If you then pass a `GrapeDto` an `IllegalArgumentException` will be thrown because it is unknown how to map a `GrapeDto`.
+Adding the missing (`@SubclassMapping`) for it will fix that.
+
+<<selection-based-on-qualifiers>> can be used to further control which methods may be chosen to map a specific subclass. For that, you will need to use one of `SubclassMapping#qualifiedByName` or `SubclassMapping#qualifiedBy`.
+
+[TIP]
+====
+If the mapping method for the subclasses does not exist it will be created and any other annotations on the fruit mapping method will be inherited by the newly generated mappings.
+====
+
+[NOTE]
+====
+Combining `@SubclassMapping` with update methods is not supported.
+If you try to use subclass mappings there will be a compile error.
+The same issue exists for the `@Context` and `@TargetType` parameters.
+====
+
+[[determining-result-type]]
+=== Determining the result type
+
+When result types have an inheritance relation, selecting either mapping method (`@Mapping`) or a factory method (`@BeanMapping`) can become ambiguous. Suppose an Apple and a Banana, which are both specializations of Fruit.
+
+.Specifying the result type of a bean mapping method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper( uses = FruitFactory.class )
+public interface FruitMapper {
+
+    @BeanMapping( resultType = Apple.class )
+    Fruit map( FruitDto source );
+
+}
+----
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class FruitFactory {
+
+    public Apple createApple() {
+        return new Apple( "Apple" );
+    }
+
+    public Banana createBanana() {
+        return new Banana( "Banana" );
+    }
+}
+----
+====
+
+So, which `Fruit` must be factorized in the mapping method `Fruit map(FruitDto source);`? A `Banana` or an `Apple`? Here's where the `@BeanMapping#resultType` comes in handy. It controls the factory method to select, or in absence of a factory method, the return type to create.
+
+[TIP]
+====
+The same mechanism is present on mapping: `@Mapping#resultType` and works like you expect it would: it selects the mapping method with the desired result type when present.
+====
+
+[TIP]
+====
+The mechanism is also present on iterable mapping and map mapping. `@IterableMapping#elementTargetType` is used to select the mapping method with the desired element in the resulting `Iterable`. For the `@MapMapping` a similar purpose is served by means of `#MapMapping#keyTargetType` and `MapMapping#valueTargetType`.
+====
+
+[[mapping-result-for-null-arguments]]
+=== Controlling mapping result for 'null' arguments
+
+MapStruct offers control over the object to create when the source argument of the mapping method equals `null`. By default `null` will be returned.
+
+However, by specifying `nullValueMappingStrategy = NullValueMappingStrategy.RETURN_DEFAULT` on `@BeanMapping`, `@IterableMapping`, `@MapMapping`, or globally on `@Mapper` or `@MapperConfig`, the mapping result can be altered to return empty *default* values. This means for:
+
+* *Bean mappings*: an 'empty' target bean will be returned, with the exception of constants and expressions, they will be populated when present.
+* *Iterables / Arrays*: an empty iterable will be returned.
+* *Maps*: an empty map will be returned.
+
+The strategy works in a hierarchical fashion. Setting `nullValueMappingStrategy` on mapping method level will override `@Mapper#nullValueMappingStrategy`, and `@Mapper#nullValueMappingStrategy` will override `@MapperConfig#nullValueMappingStrategy`.
+
+[[mapping-result-for-null-collection-or-map-arguments]]
+=== Controlling mapping result for 'null' collection or map arguments
+
+With <<mapping-result-for-null-arguments>> it is possible to control how the return type should be constructed when the source argument of the mapping method is `null`.
+That is applied for all mapping methods (bean, iterable or map mapping methods).
+
+However, MapStruct also offers a more dedicated way to control how collections / maps should be mapped.
+e.g. return default (empty) collections / maps, but return `null` for beans.
+
+For collections (iterables) this can be controlled through:
+
+* `MapperConfig#nullValueIterableMappingStrategy`
+* `Mapper#nullValueIterableMappingStrategy`
+* `IterableMapping#nullValueMappingStrategy`
+
+For maps this can be controlled through:
+
+* `MapperConfig#nullValueMapMappingStrategy`
+* `Mapper#nullValueMapMappingStrategy`
+* `MapMapping#nullValueMappingStrategy`
+
+How the value of the `NullValueMappingStrategy` is applied is the same as in <<mapping-result-for-null-arguments>>
+
+
+[[mapping-result-for-null-properties]]
+=== Controlling mapping result for 'null' properties in bean mappings (update mapping methods only).
+
+MapStruct offers control over the property to set in an `@MappingTarget` annotated target bean when the source property equals `null` or the presence check method results in 'absent'.
+
+By default the target property will be set to null.
+
+However:
+
+1. By specifying `nullValuePropertyMappingStrategy = NullValuePropertyMappingStrategy.SET_TO_DEFAULT` on `@Mapping`, `@BeanMapping`, `@Mapper` or `@MapperConfig`, the mapping result can be altered to return *default* values.
+For `List` MapStruct generates an `ArrayList`, for `Map` a `LinkedHashMap`, for arrays an empty array, for `String` `""` and for primitive / boxed types a representation of `false` or `0`.
+For all other objects an new instance is created. Please note that a default constructor is required. If not available, use the `@Mapping#defaultValue`.
+
+2. By specifying `nullValuePropertyMappingStrategy = NullValuePropertyMappingStrategy.IGNORE` on `@Mapping`, `@BeanMapping`, `@Mapper` or `@MapperConfig`, the mapping result will be equal to the original value of the `@MappingTarget` annotated target.
+
+The strategy works in a hierarchical fashion. Setting `nullValuePropertyMappingStrategy` on mapping method level will override `@Mapper#nullValuePropertyMappingStrategy`, and `@Mapper#nullValuePropertyMappingStrategy` will override `@MapperConfig#nullValuePropertyMappingStrategy`.
+
+[NOTE]
+====
+Some types of mappings (collections, maps), in which MapStruct is instructed to use a getter or adder as target accessor (see `CollectionMappingStrategy`), MapStruct will always generate a source property
+null check, regardless of the value of the `NullValuePropertyMappingStrategy`, to avoid addition of `null` to the target collection or map. Since the target is assumed to be initialised this strategy will not be applied.
+====
+
+[TIP]
+====
+`NullValuePropertyMappingStrategy` also applies when the presence checker returns `not present`.
+====
+
+[[checking-source-property-for-null-arguments]]
+=== Controlling checking result for 'null' properties in bean mapping
+
+MapStruct offers control over when to generate a `null` check. By default (`nullValueCheckStrategy = NullValueCheckStrategy.ON_IMPLICIT_CONVERSION`) a `null` check will be generated for:
+
+* direct setting of source value to target value when target is primitive and source is not.
+* applying type conversion and then:
+.. calling the setter on the target.
+.. calling another type conversion and subsequently calling the setter on the target.
+.. calling a mapping method and subsequently calling the setter on the target.
+
+First calling a mapping method on the source property is not protected by a null check. Therefore generated mapping methods will do a null check prior to carrying out mapping on a source property. Handwritten mapping methods must take care of null value checking. They have the possibility to add 'meaning' to `null`. For instance: mapping `null` to a default value.
+
+The option `nullValueCheckStrategy = NullValueCheckStrategy.ALWAYS` will always include a null check when source is non primitive, unless a source presence checker is defined on the source bean.
+
+The strategy works in a hierarchical fashion. `@Mapping#nullValueCheckStrategy` will override `@BeanMapping#nullValueCheckStrategy`, `@BeanMapping#nullValueCheckStrategy` will override `@Mapper#nullValueCheckStrategy` and `@Mapper#nullValueCheckStrategy` will override `@MapperConfig#nullValueCheckStrategy`.
+
+[[source-presence-check]]
+=== Source presence checking
+Some frameworks generate bean properties that have a source presence checker. Often this is in the form of a method `hasXYZ`, `XYZ` being a property on the source bean in a bean mapping method. MapStruct will call this `hasXYZ` instead of performing a `null` check when it finds such `hasXYZ` method.
+
+[TIP]
+====
+The source presence checker name can be changed in the MapStruct service provider interface (SPI). It can also be deactivated in this way.
+====
+
+[NOTE]
+====
+Some types of mappings (collections, maps), in which MapStruct is instructed to use a getter or adder as target accessor (see `CollectionMappingStrategy`), MapStruct will always generate a source property
+null check, regardless the value of the `NullValueCheckStrategy` to avoid addition of `null` to the target collection or map.
+====
+
+[[conditional-mapping]]
+=== Conditional Mapping
+
+Conditional Mapping is a type of <<source-presence-check>>.
+The difference is that it allows users to write custom condition methods that will be invoked to check if a property needs to be mapped or not.
+Conditional mapping can also be used to check if a source parameter should be mapped or not.
+
+A custom condition method for properties is a method that is annotated with `org.mapstruct.Condition` and returns `boolean`.
+A custom condition method for source parameters is annotated with `org.mapstruct.SourceParameterCondition`, `org.mapstruct.Condition(appliesTo = org.mapstruct.ConditionStrategy#SOURCE_PARAMETERS)` or meta-annotated with `Condition(appliesTo = ConditionStrategy#SOURCE_PARAMETERS)`
+
+e.g. if you only want to map a String property when it is not `null` and not empty then you can do something like:
+
+.Mapper using custom condition check method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    CarDto carToCarDto(Car car);
+
+    @Condition
+    default boolean isNotEmpty(String value) {
+        return value != null && !value.isEmpty();
+    }
+}
+----
+====
+
+The generated mapper will look like:
+
+.Custom condition check in generated implementation
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class CarMapperImpl implements CarMapper {
+
+    @Override
+    public CarDto carToCarDto(Car car) {
+        if ( car == null ) {
+            return null;
+        }
+
+        CarDto carDto = new CarDto();
+
+        if ( isNotEmpty( car.getOwner() ) ) {
+            carDto.setOwner( car.getOwner() );
+        }
+
+        // Mapping of other properties
+
+        return carDto;
+    }
+}
+----
+====
+
+When using this in combination with an update mapping method it will replace the `null-check` there, for example:
+
+.Update mapper using custom condition check method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    CarDto carToCarDto(Car car, @MappingTarget CarDto carDto);
+
+    @Condition
+    default boolean isNotEmpty(String value) {
+        return value != null && !value.isEmpty();
+    }
+}
+----
+====
+
+The generated update mapper will look like:
+
+.Custom condition check in generated implementation
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class CarMapperImpl implements CarMapper {
+
+    @Override
+    public CarDto carToCarDto(Car car, CarDto carDto) {
+        if ( car == null ) {
+            return carDto;
+        }
+
+        if ( isNotEmpty( car.getOwner() ) ) {
+            carDto.setOwner( car.getOwner() );
+        } else {
+            carDto.setOwner( null );
+        }
+
+        // Mapping of other properties
+
+        return carDto;
+    }
+}
+----
+====
+
+Additionally `@TargetPropertyName` or `@SourcePropertyName` of type `java.lang.String` can be used in custom condition check method:
+
+.Mapper using custom condition check method with `@TargetPropertyName` and `@SourcePropertyName`
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    @Mapping(target = "owner", source = "ownerName")
+    CarDto carToCarDto(Car car, @MappingTarget CarDto carDto);
+
+    @Condition
+    default boolean isNotEmpty(
+        String value,
+        @TargetPropertyName String targetPropertyName,
+        @SourcePropertyName String sourcePropertyName
+    ) {
+
+        if ( targetPropertyName.equals( "owner" )
+             && sourcePropertyName.equals( "ownerName" ) ) {
+
+           return value != null
+                    && !value.isEmpty()
+                    && !value.equals( value.toLowerCase() );
+        }
+        return value != null && !value.isEmpty();
+    }
+}
+----
+====
+
+The generated mapper with `@TargetPropertyName` and `@SourcePropertyName` will look like:
+
+.Custom condition check in generated implementation
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class CarMapperImpl implements CarMapper {
+
+    @Override
+    public CarDto carToCarDto(Car car, CarDto carDto) {
+        if ( car == null ) {
+            return carDto;
+        }
+
+        if ( isNotEmpty( car.getOwner(), "owner", "ownerName" ) ) {
+            carDto.setOwner( car.getOwner() );
+        } else {
+            carDto.setOwner( null );
+        }
+
+        // Mapping of other properties
+
+        return carDto;
+    }
+}
+----
+====
+
+[IMPORTANT]
+====
+If there is a custom `@Condition` method applicable for the property it will have a precedence over a presence check method in the bean itself.
+====
+
+[NOTE]
+====
+Methods annotated with `@Condition` in addition to the value of the source property can also have the source parameter as an input.
+
+`@TargetPropertyName` and `@SourcePropertyName` parameters can only be used in `@Condition` methods.
+====
+
+<<selection-based-on-qualifiers>> is also valid for `@Condition` methods.
+In order to use a more specific condition method you will need to use one of `Mapping#conditionQualifiedByName` or `Mapping#conditionQualifiedBy`.
+
+If we want to only map cars that have an id provided then we can do something like:
+
+
+.Mapper using custom condition source parameter check method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    CarDto carToCarDto(Car car);
+
+    @SourceParameterCondition
+    default boolean hasCar(Car car) {
+        return car != null && car.getId() != null;
+    }
+}
+----
+====
+
+The generated mapper will look like:
+
+.Custom condition source parameter check generated implementation
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class CarMapperImpl implements CarMapper {
+
+    @Override
+    public CarDto carToCarDto(Car car) {
+        if ( !hasCar( car ) ) {
+            return null;
+        }
+
+        CarDto carDto = new CarDto();
+
+        carDto.setOwner( car.getOwner() );
+
+        // Mapping of other properties
+
+        return carDto;
+    }
+}
+----
+====
+
+[[exceptions]]
+=== Exceptions
+
+Calling applications may require handling of exceptions when calling a mapping method. These exceptions could be thrown by hand-written logic and by the generated built-in mapping methods or type-conversions of MapStruct. When the calling application requires handling of exceptions, a throws clause can be defined in the mapping method:
+
+.Mapper using custom method declaring checked exception
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper(uses = HandWritten.class)
+public interface CarMapper {
+
+    CarDto carToCarDto(Car car) throws GearException;
+}
+----
+====
+
+The hand written logic might look like this:
+
+.Custom mapping method declaring checked exception
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class HandWritten {
+
+    private static final String[] GEAR = {"ONE", "TWO", "THREE", "OVERDRIVE", "REVERSE"};
+
+    public String toGear(Integer gear) throws GearException, FatalException {
+        if ( gear == null ) {
+            throw new FatalException("null is not a valid gear");
+        }
+
+        if ( gear < 0 && gear > GEAR.length ) {
+            throw new GearException("invalid gear");
+        }
+        return GEAR[gear];
+    }
+}
+----
+====
+
+MapStruct now, wraps the `FatalException` in a `try-catch` block and rethrows an unchecked `RuntimeException`. MapStruct delegates handling of the `GearException` to the application logic because it is defined as throws clause in the `carToCarDto` method:
+
+.try-catch block in generated implementation
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+@Override
+public CarDto carToCarDto(Car car) throws GearException {
+    if ( car == null ) {
+        return null;
+    }
+
+    CarDto carDto = new CarDto();
+    try {
+        carDto.setGear( handWritten.toGear( car.getGear() ) );
+    }
+    catch ( FatalException e ) {
+        throw new RuntimeException( e );
+    }
+
+    return carDto;
+}
+----
+====
+
+Some **notes** on null checks. MapStruct does provide null checking only when required: when applying type-conversions or constructing a new type by invoking its constructor. This means that the user is responsible in hand-written code for returning valid non-null objects. Also null objects can be handed to hand-written code, since MapStruct does not want to make assumptions on the meaning assigned by the user to a null object. Hand-written code has to deal with this.

documentation/src/main/asciidoc/chapter-11-reusing-mapping-configurations.asciidoc

@@ -0,0 +1,167 @@
+== Reusing mapping configurations
+
+This chapter discusses different means of reusing mapping configurations for several mapping methods: "inheritance" of configuration from other methods and sharing central configuration between multiple mapper types.
+
+[[mapping-configuration-inheritance]]
+=== Mapping configuration inheritance
+
+Method-level configuration annotations such as `@Mapping`, `@BeanMapping`, `@IterableMapping`, etc., can be *inherited* from one mapping method to a *similar* method using the annotation `@InheritConfiguration`:
+
+.Update method inheriting its configuration
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    @Mapping(target = "numberOfSeats", source = "seatCount")
+    Car carDtoToCar(CarDto car);
+
+    @InheritConfiguration
+    void carDtoIntoCar(CarDto carDto, @MappingTarget Car car);
+}
+----
+====
+
+The example above declares a mapping method `carDtoToCar()` with a configuration to define how the property `numberOfSeats` in the type `Car` shall be mapped. The update method that performs the mapping on an existing instance of `Car` needs the same configuration to successfully map all properties. Declaring `@InheritConfiguration` on the method lets MapStruct search for inheritance candidates to apply the annotations of the method that is inherited from.
+
+One method *A* can inherit the configuration from another method *B* if all types of *A* (source types and result type) are assignable to the corresponding types of *B*.
+
+Methods that are considered for inheritance need to be defined in the current mapper, a super class/interface, or in the shared configuration interface (as described in <<shared-configurations>>).
+
+In case more than one method is applicable as source for the inheritance, the method name must be specified within the annotation: `@InheritConfiguration( name = "carDtoToCar" )`.
+
+A method can use `@InheritConfiguration` and override or amend the configuration by additionally applying `@Mapping`, `@BeanMapping`, etc.
+
+[NOTE]
+====
+`@InheritConfiguration` cannot refer to methods in a used mapper.
+====
+
+[[inverse-mappings]]
+=== Inverse mappings
+
+In case of bi-directional mappings, e.g. from entity to DTO and from DTO to entity, the mapping rules for the forward method and the reverse method are often similar and can simply be inversed by switching `source` and `target`.
+
+Use the annotation `@InheritInverseConfiguration` to indicate that a method shall inherit the inverse configuration of the corresponding reverse method.
+
+In the example below, there is no need to write the inverse mapping manually. Think of a case where there are several mappings, so writing the inverse ones can be cumbersome and error prone.
+
+.Inverse mapping method inheriting its configuration and ignoring some of them
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    @Mapping(target = "seatCount", source = "numberOfSeats")
+    CarDto carToDto(Car car);
+
+    @InheritInverseConfiguration
+    @Mapping(target = "numberOfSeats", ignore = true)
+    Car carDtoToCar(CarDto carDto);
+}
+----
+====
+
+Here the `carDtoToCar()` method is the reverse mapping method for `carToDto()`. Note that any attribute mappings from `carToDto()` will be applied to the corresponding reverse mapping method as well. They are automatically reversed and copied to the method with the `@InheritInverseConfiguration` annotation.
+
+Specific mappings from the inversed method can (optionally) be overridden by  `ignore`, `expression` or `constant` in the mapping, e.g. like this: `@Mapping(target = "numberOfSeats", ignore=true)`.
+
+A method *A* is considered a *reverse* method of a method *B*, if the result type of *A* is the *same* as the single source type of *B* and if the single source type of *A* is the *same* as the result type of *B*.
+
+Methods that are considered for inverse inheritance need to be defined in the current mapper, a super class/interface.
+
+If multiple methods qualify, the method from which to inherit the configuration needs to be specified using the `name` property like this: `@InheritInverseConfiguration(name = "carToDto")`.
+
+`@InheritConfiguration` takes, in case of conflict precedence over `@InheritInverseConfiguration`.
+
+Configurations are inherited transitively. So if method `C` defines a mapping `@Mapping( target = "x", ignore = true)`, `B` defines a mapping `@Mapping( target = "y", ignore = true)`, then if `A` inherits from `B` inherits from `C`, `A` will inherit mappings for both property `x` and `y`.
+
+`@Mapping#expression`, `@Mapping#defaultExpression`, `@Mapping#defaultValue` and `@Mapping#constant` are excluded (silently ignored) in `@InheritInverseConfiguration`.
+
+`@Mapping#ignore` is only applied when `@Mapping#source` is also present in `@InheritInverseConfiguration`.
+
+Reverse mapping of nested source properties is experimental as of the 1.1.0.Beta2 release. Reverse mapping will take place automatically when the source property name and target property name are identical. Otherwise, `@Mapping` should specify both the target name and source name. In all cases, a suitable mapping method needs to be in place for the reverse mapping.
+
+[NOTE]
+====
+`@InheritInverseConfiguration` cannot refer to methods in a used mapper.
+====
+
+[[shared-configurations]]
+=== Shared configurations
+
+MapStruct offers the possibility to define a shared configuration by pointing to a central interface annotated with `@MapperConfig`. For a mapper to use the shared configuration, the configuration interface needs to be defined in the `@Mapper#config` property.
+
+The `@MapperConfig` annotation has the same attributes as the `@Mapper` annotation. Any attributes not given via `@Mapper` will be inherited from the shared configuration. Attributes specified in `@Mapper` take precedence over the attributes specified via the referenced configuration class. List properties such as `uses` are simply combined:
+
+.Mapper configuration class and mapper using it
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@MapperConfig(
+    uses = CustomMapperViaMapperConfig.class,
+    unmappedTargetPolicy = ReportingPolicy.ERROR
+)
+public interface CentralConfig {
+}
+----
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper(config = CentralConfig.class, uses = { CustomMapperViaMapper.class } )
+// Effective configuration:
+// @Mapper(
+//     uses = { CustomMapperViaMapper.class, CustomMapperViaMapperConfig.class },
+//     unmappedTargetPolicy = ReportingPolicy.ERROR
+// )
+public interface SourceTargetMapper {
+  ...
+}
+
+----
+====
+
+The interface holding the `@MapperConfig` annotation may also declare *prototypes* of mapping methods that can be used to inherit method-level mapping annotations from. Such prototype methods are not meant to be implemented or used as part of the mapper API.
+
+.Mapper configuration class with prototype methods
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@MapperConfig(
+    uses = CustomMapperViaMapperConfig.class,
+    unmappedTargetPolicy = ReportingPolicy.ERROR,
+    mappingInheritanceStrategy = MappingInheritanceStrategy.AUTO_INHERIT_FROM_CONFIG
+)
+public interface CentralConfig {
+
+    // Not intended to be generated, but to carry inheritable mapping annotations:
+    @Mapping(target = "primaryKey", source = "technicalKey")
+    BaseEntity anyDtoToEntity(BaseDto dto);
+}
+----
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper(config = CentralConfig.class, uses = { CustomMapperViaMapper.class } )
+public interface SourceTargetMapper {
+
+    @Mapping(target = "numberOfSeats", source = "seatCount")
+    // additionally inherited from CentralConfig, because Car extends BaseEntity and CarDto extends BaseDto:
+    // @Mapping(target = "primaryKey", source = "technicalKey")
+    Car toCar(CarDto car)
+}
+----
+====
+
+The attributes `@Mapper#mappingInheritanceStrategy()` / `@MapperConfig#mappingInheritanceStrategy()` configure when the method-level mapping configuration annotations are inherited from prototype methods in the interface to methods in the mapper:
+
+* `EXPLICIT` (default): the configuration will only be inherited, if the target mapping method is annotated with `@InheritConfiguration` and the source and target types are assignable to the corresponding types of the prototype method, all as described in <<mapping-configuration-inheritance>>.
+* `AUTO_INHERIT_FROM_CONFIG`: the configuration will be inherited automatically, if the source and target types of the target mapping method are assignable to the corresponding types of the prototype method. If multiple prototype methods match, the ambiguity must be resolved using `@InheritConfiguration(name = ...)` which will cause `AUTO_INHERIT_FROM_CONFIG` to be ignored.
+* `AUTO_INHERIT_REVERSE_FROM_CONFIG`: the inverse configuration will be inherited automatically, if the source and target types of the target mapping method are assignable to the corresponding types of the prototype method. If multiple prototype methods match, the ambiguity must be resolved using `@InheritInverseConfiguration(name = ...)` which will cause ``AUTO_INHERIT_REVERSE_FROM_CONFIG` to be ignored.
+* `AUTO_INHERIT_ALL_FROM_CONFIG`: both the configuration and the inverse configuration will be inherited automatically. The same rules apply as for `AUTO_INHERIT_FROM_CONFIG` or `AUTO_INHERIT_REVERSE_FROM_CONFIG`.

documentation/src/main/asciidoc/chapter-12-customizing-mapping.asciidoc

@@ -0,0 +1,271 @@
+== Customizing mappings
+
+Sometimes it's needed to apply custom logic before or after certain mapping methods. MapStruct provides two ways for doing so: decorators which allow for a type-safe customization of specific mapping methods and the before-mapping and after-mapping lifecycle methods which allow for a generic customization of mapping methods with given source or target types.
+
+[[customizing-mappers-using-decorators]]
+=== Mapping customization with decorators
+
+In certain cases it may be required to customize a generated mapping method, e.g. to set an additional property in the target object which can't be set by a generated method implementation. MapStruct supports this requirement using decorators.
+
+[TIP]
+When working with the component model `cdi`, use https://docs.jboss.org/cdi/spec/1.0/html/decorators.html[CDI decorators] with MapStruct mappers instead of the `@DecoratedWith` annotation described here.
+
+To apply a decorator to a mapper class, specify it using the `@DecoratedWith` annotation.
+
+.Applying a decorator
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+@DecoratedWith(PersonMapperDecorator.class)
+public interface PersonMapper {
+
+    PersonMapper INSTANCE = Mappers.getMapper( PersonMapper.class );
+
+    PersonDto personToPersonDto(Person person);
+
+    AddressDto addressToAddressDto(Address address);
+}
+----
+====
+
+The decorator must be a sub-type of the decorated mapper type. You can make it an abstract class which allows to only implement those methods of the mapper interface which you want to customize. For all non-implemented methods, a simple delegation to the original mapper will be generated using the default generation routine.
+
+The `PersonMapperDecorator` shown below customizes the `personToPersonDto()`. It sets an additional attribute which is not present in the source type of the mapping. The `addressToAddressDto()` method is not customized.
+
+.Implementing a decorator
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public abstract class PersonMapperDecorator implements PersonMapper {
+
+    private final PersonMapper delegate;
+
+    public PersonMapperDecorator(PersonMapper delegate) {
+        this.delegate = delegate;
+    }
+
+    @Override
+    public PersonDto personToPersonDto(Person person) {
+        PersonDto dto = delegate.personToPersonDto( person );
+        dto.setFullName( person.getFirstName() + " " + person.getLastName() );
+        return dto;
+    }
+}
+----
+====
+
+The example shows how you can optionally inject a delegate with the generated default implementation and use this delegate in your customized decorator methods.
+
+For a mapper with `componentModel = "default"`, define a constructor with a single parameter which accepts the type of the decorated mapper.
+
+When working with the component models `spring` or `jsr330`, this needs to be handled differently.
+
+[[decorators-with-spring]]
+==== Decorators with the Spring component model
+
+When using `@DecoratedWith` on a mapper with component model `spring`, the generated implementation of the original mapper is annotated with the Spring annotation `@Qualifier("delegate")`. To autowire that bean in your decorator, add that qualifier annotation as well:
+
+.Spring-based decorator
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public abstract class PersonMapperDecorator implements PersonMapper {
+
+     @Autowired
+     @Qualifier("delegate")
+     private PersonMapper delegate;
+
+     @Override
+     public PersonDto personToPersonDto(Person person) {
+         PersonDto dto = delegate.personToPersonDto( person );
+         dto.setName( person.getFirstName() + " " + person.getLastName() );
+
+         return dto;
+     }
+ }
+----
+====
+
+The generated class that extends the decorator is annotated with Spring's `@Primary` annotation. To autowire the decorated mapper in the application, nothing special needs to be done:
+
+.Using a decorated mapper
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Autowired
+private PersonMapper personMapper; // injects the decorator, with the injected original mapper
+----
+====
+
+[[decorators-with-jsr-330]]
+==== Decorators with the JSR 330 component model
+
+JSR 330 doesn't specify qualifiers and only allows to specifically name the beans. Hence, the generated implementation of the original mapper is annotated with `@Named("fully-qualified-name-of-generated-implementation")` (please note that when using a decorator, the class name of the mapper implementation ends with an underscore). To inject that bean in your decorator, add the same annotation to the delegate field (e.g. by copy/pasting it from the generated class):
+
+.JSR 330 based decorator
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public abstract class PersonMapperDecorator implements PersonMapper {
+
+    @Inject
+    @Named("org.examples.PersonMapperImpl_")
+    private PersonMapper delegate;
+
+    @Override
+    public PersonDto personToPersonDto(Person person) {
+        PersonDto dto = delegate.personToPersonDto( person );
+        dto.setName( person.getFirstName() + " " + person.getLastName() );
+
+        return dto;
+    }
+}
+----
+====
+
+Unlike with the other component models, the usage site must be aware if a mapper is decorated or not, as for decorated mappers, the parameterless `@Named` annotation must be added to select the decorator to be injected:
+
+.Using a decorated mapper with JSR 330
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Inject
+@Named
+private PersonMapper personMapper; // injects the decorator, with the injected original mapper
+----
+====
+
+[[customizing-mappings-with-before-and-after]]
+=== Mapping customization with before-mapping and after-mapping methods
+
+Decorators may not always fit the needs when it comes to customizing mappers. For example, if you need to perform the customization not only for a few selected methods, but for all methods that map specific super-types: in that case, you can use *callback methods* that are invoked before the mapping starts or after the mapping finished.
+
+Callback methods can be implemented in the abstract mapper itself, in a type reference in `Mapper#uses`, or in a type used as `@Context` parameter.
+
+.Mapper with @BeforeMapping and @AfterMapping hooks
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public abstract class VehicleMapper {
+
+    @BeforeMapping
+    protected void flushEntity(AbstractVehicle vehicle) {
+        // I would call my entity manager's flush() method here to make sure my entity
+        // is populated with the right @Version before I let it map into the DTO
+    }
+
+    @AfterMapping
+    protected void fillTank(AbstractVehicle vehicle, @MappingTarget AbstractVehicleDto result) {
+        result.fuelUp( new Fuel( vehicle.getTankCapacity(), vehicle.getFuelType() ) );
+    }
+
+    public abstract CarDto toCarDto(Car car);
+}
+
+// Generates something like this:
+public class VehicleMapperImpl extends VehicleMapper {
+
+    public CarDto toCarDto(Car car) {
+        flushEntity( car );
+
+        if ( car == null ) {
+            return null;
+        }
+
+        CarDto carDto = new CarDto();
+        // attributes mapping ...
+
+        fillTank( car, carDto );
+
+        return carDto;
+    }
+}
+----
+====
+
+If the `@BeforeMapping` / `@AfterMapping` method has parameters, the method invocation is only generated if the return type of the method (if non-`void`) is assignable to the return type of the mapping method and all parameters can be *assigned* by the source or target parameters of the mapping method:
+
+* A parameter annotated with `@MappingTarget` is populated with the target instance of the mapping.
+* A parameter annotated with `@TargetType` is populated with the target type of the mapping.
+* Parameters annotated with `@Context` are populated with the context parameters of the mapping method.
+* Any other parameter is populated with a source parameter of the mapping.
+
+For non-`void` methods, the return value of the method invocation is returned as the result of the mapping method if it is not `null`.
+
+As with mapping methods, it is possible to specify type parameters for before/after-mapping methods.
+
+.Mapper with @AfterMapping hook that returns a non-null value
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public abstract class VehicleMapper {
+
+    @PersistenceContext
+    private EntityManager entityManager;
+
+    @AfterMapping
+    protected <T> T attachEntity(@MappingTarget T entity) {
+        return entityManager.merge(entity);
+    }
+
+    public abstract CarDto toCarDto(Car car);
+}
+
+// Generates something like this:
+public class VehicleMapperImpl extends VehicleMapper {
+
+    public CarDto toCarDto(Car car) {
+        if ( car == null ) {
+            return null;
+        }
+
+        CarDto carDto = new CarDto();
+        // attributes mapping ...
+
+        CarDto target = attachEntity( carDto );
+        if ( target != null ) {
+            return target;
+        }
+
+        return carDto;
+    }
+}
+----
+====
+
+All before/after-mapping methods that *can* be applied to a mapping method *will* be used. <<selection-based-on-qualifiers>> can be used to further control which methods may be chosen and which not. For that, the qualifier annotation needs to be applied to the before/after-method and referenced in `BeanMapping#qualifiedBy` or `IterableMapping#qualifiedBy`.
+
+The order of the method invocation is determined primarily by their variant:
+
+1. `@BeforeMapping` methods without parameters, a `@MappingTarget` parameter or a `@TargetType` parameter are called before any null-checks on source parameters and constructing a new target bean.
+2. `@BeforeMapping` methods with a `@MappingTarget` parameter are called after constructing a new target bean.
+3. `@AfterMapping` methods are called at the end of the mapping method before the last `return` statement.
+
+Within those groups, the method invocations are ordered by their location of definition:
+
+1. Methods declared on `@Context` parameters, ordered by the parameter order.
+2. Methods implemented in the mapper itself.
+3. Methods from types referenced in `Mapper#uses()`, in the order of the type declaration in the annotation.
+4. Methods declared in one type are used after methods declared in their super-type.
+
+*Important:* the order of methods declared within one type can not be guaranteed, as it depends on the compiler and the processing environment implementation.
+
+[NOTE]
+====
+Before/After-mapping methods can also be used with builders:
+
+* `@BeforeMapping` methods with a `@MappingTarget` parameter of the real target will not be invoked because it is only available after the mapping was already performed.
+* To be able to modify the object that is going to be built, the `@AfterMapping` annotated method must have the builder as `@MappingTarget` annotated parameter. The `build` method is called when the `@AfterMapping` annotated method scope finishes.
+* The `@AfterMapping` annotated method can also have the real target as `@TargetType` or `@MappingTarget`. It will be invoked after the real target was built (first the methods annotated with `@TargetType`, then the methods annotated with `@MappingTarget`)
+====

documentation/src/main/asciidoc/chapter-13-using-mapstruct-spi.asciidoc

@@ -0,0 +1,424 @@
+[[using-spi]]
+== Using the MapStruct SPI
+
+To use a custom SPI implementation, it must be located in a separate JAR file together with a file named after the SPI (e.g. `org.mapstruct.ap.spi.AccessorNamingStrategy`) in `META-INF/services/` with the fully qualified name of your custom implementation as content (e.g. `org.mapstruct.example.CustomAccessorNamingStrategy`). This JAR file needs to be added to the annotation processor classpath (i.e. add it next to the place where you added the mapstruct-processor jar).
+
+
+[NOTE]
+====
+It might also be necessary to add the jar to your IDE's annotation processor factory path. Otherwise you might get an error stating that it cannot be found, while a run using your build tool does succeed.
+====
+
+=== Custom Accessor Naming Strategy
+
+SPI name: `org.mapstruct.ap.spi.AccessorNamingStrategy`
+
+MapStruct offers the possibility to override the `AccessorNamingStrategy` via the Service Provider Interface (SPI). A nice example is the use of the fluent API on the source object `GolfPlayer` and `GolfPlayerDto` below.
+
+.Source object GolfPlayer with fluent API.
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class GolfPlayer {
+
+    private double handicap;
+    private String name;
+
+    public double handicap() {
+        return handicap;
+    }
+
+    public GolfPlayer withHandicap(double handicap) {
+        this.handicap = handicap;
+        return this;
+    }
+
+    public String name() {
+        return name;
+    }
+
+    public GolfPlayer withName(String name) {
+        this.name = name;
+        return this;
+    }
+}
+----
+====
+
+.Source object GolfPlayerDto with fluent API.
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class GolfPlayerDto {
+
+    private double handicap;
+    private String name;
+
+    public double handicap() {
+        return handicap;
+    }
+
+    public GolfPlayerDto withHandicap(double handicap) {
+        this.handicap = handicap;
+        return this;
+    }
+
+    public String name() {
+        return name;
+    }
+
+    public GolfPlayerDto withName(String name) {
+        this.name = name;
+        return this;
+    }
+}
+----
+====
+
+We want `GolfPlayer` to be mapped to a target object `GolfPlayerDto` similar like we 'always' do this:
+
+.Source object with fluent API.
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface GolfPlayerMapper {
+
+    GolfPlayerMapper INSTANCE = Mappers.getMapper( GolfPlayerMapper.class );
+
+    GolfPlayerDto toDto(GolfPlayer player);
+
+    GolfPlayer toPlayer(GolfPlayerDto player);
+
+}
+----
+====
+
+This can be achieved with implementing the SPI `org.mapstruct.ap.spi.AccessorNamingStrategy` as in the following example. Here's an implemented `org.mapstruct.ap.spi.AccessorNamingStrategy`:
+
+.CustomAccessorNamingStrategy
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+/**
+ * A custom {@link AccessorNamingStrategy} recognizing getters in the form of {@code property()} and setters in the
+ * form of {@code withProperty(value)}.
+ */
+public class CustomAccessorNamingStrategy extends DefaultAccessorNamingStrategy {
+
+    @Override
+    public boolean isGetterMethod(ExecutableElement method) {
+        String methodName = method.getSimpleName().toString();
+        return !methodName.startsWith( "with" ) && method.getReturnType().getKind() != TypeKind.VOID;
+    }
+
+    @Override
+    public boolean isSetterMethod(ExecutableElement method) {
+        String methodName = method.getSimpleName().toString();
+        return methodName.startsWith( "with" ) && methodName.length() > 4;
+    }
+
+    @Override
+    public String getPropertyName(ExecutableElement getterOrSetterMethod) {
+        String methodName = getterOrSetterMethod.getSimpleName().toString();
+        return IntrospectorUtils.decapitalize( methodName.startsWith( "with" ) ? methodName.substring(  4 ) : methodName );
+    }
+}
+----
+====
+The `CustomAccessorNamingStrategy` makes use of the `DefaultAccessorNamingStrategy` (also available in mapstruct-processor) and relies on that class to leave most of the default behaviour unchanged.
+
+[TIP]
+Fore more details: The example above is present in our examples repository (https://github.com/mapstruct/mapstruct-examples).
+
+[[mapping-exclusion-provider]]
+=== Mapping Exclusion Provider
+
+SPI name: `org.mapstruct.ap.spi.MappingExclusionProvider`
+
+MapStruct offers the possibility to override the `MappingExclusionProvider` via the Service Provider Interface (SPI).
+A nice example is to not allow MapStruct to create an automatic sub-mapping for a certain type,
+i.e. MapStruct will not try to generate an automatic sub-mapping method for an excluded type.
+
+[NOTE]
+====
+The `DefaultMappingExclusionProvider` will exclude all types under the `java` or `javax` packages.
+This means that MapStruct will not try to generate an automatic sub-mapping method between some custom type and some type declared in the Java class library.
+====
+
+.Source object
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+include::{processor-ap-test}/nestedbeans/exclusions/custom/Source.java[tag=documentation]
+----
+====
+
+.Target object
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+include::{processor-ap-test}/nestedbeans/exclusions/custom/Target.java[tag=documentation]
+----
+====
+
+.Mapper definition
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+include::{processor-ap-test}/nestedbeans/exclusions/custom/ErroneousCustomExclusionMapper.java[tag=documentation]
+----
+====
+
+We want to exclude the `NestedTarget` from the automatic sub-mapping method generation.
+
+.CustomMappingExclusionProvider
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+include::{processor-ap-test}/nestedbeans/exclusions/custom/CustomMappingExclusionProvider.java[tag=documentation]
+----
+====
+
+
+[[custom-builder-provider]]
+=== Custom Builder Provider
+
+SPI name: org.mapstruct.ap.spi.BuilderProvider
+
+MapStruct offers the possibility to override the `DefaultProvider` via the Service Provider Interface (SPI).
+A nice example is to provide support for a custom builder strategy.
+
+.Custom Builder Provider which disables Builder support
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+include::{processor-ap-main}/spi/NoOpBuilderProvider.java[tag=documentation]
+----
+====
+
+[[custom-enum-naming-strategy]]
+=== Custom Enum Naming Strategy
+
+SPI name: `org.mapstruct.ap.spi.EnumMappingStrategy`
+
+MapStruct offers the possibility to override the `EnumMappingStrategy` via the Service Provider Interface (SPI).
+This can be used when you have certain enums that follow some conventions within your organization.
+For example all enums which implement an interface named `CustomEnumMarker` are prefixed with `CUSTOM_`
+and the default value for them when mapping from `null` is `UNSPECIFIED`
+
+.Normal Enum
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public enum CheeseType {
+    BRIE,
+    ROQUEFORT;
+}
+----
+====
+
+.Custom marker enum
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public enum CustomCheeseType implements CustomEnumMarker {
+
+    UNSPECIFIED,
+    CUSTOM_BRIE,
+    CUSTOM_ROQUEFORT;
+}
+----
+====
+
+We want `CheeseType` and `CustomCheeseType` to be mapped without the need to manually define the value mappings:
+
+.Custom enum mapping
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CheeseTypeMapper {
+
+    CheeseType map(CustomCheeseType cheese);
+
+    CustomCheeseType map(CheeseType cheese);
+}
+----
+====
+
+This can be achieved with implementing the SPI `org.mapstruct.ap.spi.EnumMappingStrategy` as in the following example.
+Here’s an implemented `org.mapstruct.ap.spi.EnumMappingStrategy`:
+
+.Custom enum naming strategy
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class CustomEnumMappingStrategy extends DefaultEnumMappingStrategy {
+
+    @Override
+    public String getDefaultNullEnumConstant(TypeElement enumType) {
+        if ( isCustomEnum( enumType ) ) {
+            return "UNSPECIFIED";
+        }
+
+        return super.getDefaultNullEnumConstant( enumType );
+    }
+
+    @Override
+    public String getEnumConstant(TypeElement enumType, String enumConstant) {
+        if ( isCustomEnum( enumType ) ) {
+            return getCustomEnumConstant( enumConstant );
+        }
+        return super.getEnumConstant( enumType, enumConstant );
+    }
+     protected String getCustomEnumConstant(String enumConstant) {
+        if ( "UNSPECIFIED".equals( enumConstant ) ) {
+            return MappingConstantsGem.NULL;
+        }
+         return enumConstant.replace( "CUSTOM_", "" );
+    }
+     protected boolean isCustomEnum(TypeElement enumType) {
+        for ( TypeMirror enumTypeInterface : enumType.getInterfaces() ) {
+            if ( typeUtils.asElement( enumTypeInterface ).getSimpleName().contentEquals( "CustomEnumMarker" ) ) {
+                return true;
+            }
+        }
+         return false;
+    }
+}
+----
+====
+
+The generated code then for the `CheeseMapper` looks like:
+
+.Generated CheeseTypeMapper
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class CheeseTypeMapperImpl implements CheeseTypeMapper {
+
+    @Override
+    public CheeseType map(CustomCheeseType cheese) {
+        if ( cheese == null ) {
+            return null;
+        }
+
+        CheeseType cheeseType;
+
+        switch ( cheese ) {
+            case UNRECOGNIZED: cheeseType = null;
+            break;
+            case CUSTOM_BRIE: cheeseType = CheeseType.BRIE;
+            break;
+            case CUSTOM_ROQUEFORT: cheeseType = CheeseType.ROQUEFORT;
+            break;
+            default: throw new IllegalArgumentException( "Unexpected enum constant: " + cheese );
+        }
+
+        return cheeseType;
+    }
+
+    @Override
+    public CustomCheeseType map(CheeseType cheese) {
+        if ( cheese == null ) {
+            return CustomCheeseType.UNSPECIFIED;
+        }
+
+        CustomCheeseType customCheeseType;
+
+        switch ( cheese ) {
+            case BRIE: customCheeseType = CustomCheeseType.CUSTOM_BRIE;
+            break;
+            case ROQUEFORT: customCheeseType = CustomCheeseType.CUSTOM_ROQUEFORT;
+            break;
+            default: throw new IllegalArgumentException( "Unexpected enum constant: " + cheese );
+        }
+
+        return customCheeseType;
+    }
+}
+----
+====
+
+[[custom-enum-transformation-strategy]]
+=== Custom Enum Transformation Strategy
+
+SPI name: `org.mapstruct.ap.spi.EnumTransformationStrategy`
+
+MapStruct offers the possibility to other transformations strategies by implementing `EnumTransformationStrategy` via the Service Provider Interface (SPI).
+A nice example is to provide support for a custom transformation strategy.
+
+.Custom Enum Transformation Strategy which lower-cases the value and applies a suffix
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+include::{processor-ap-test}/value/nametransformation/CustomEnumTransformationStrategy.java[tag=documentation]
+----
+====
+
+[[additional-supported-options-provider]]
+=== Additional Supported Options Provider
+
+SPI name: `org.mapstruct.ap.spi.AdditionalSupportedOptionsProvider`
+
+MapStruct offers the ability to pass through declared compiler args (or "options") provided to the MappingProcessor
+to the individual SPIs, by implementing `AdditionalSupportedOptionsProvider` via the Service Provider Interface (SPI).
+
+.Custom Additional Supported Options Provider that declares `myorg.custom.defaultNullEnumConstant` as an option to pass through
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+include::{processor-ap-test}/additionalsupportedoptions/CustomAdditionalSupportedOptionsProvider.java[tag=documentation]
+----
+====
+
+The value of this option is provided by including an `arg` to the `compilerArgs` tag when defining your custom SPI
+implementation.
+
+.Example maven configuration with additional options
+====
+[source, maven, linenums]
+[subs="verbatim,attributes"]
+----
+<configuration>
+    <annotationProcessorPaths>
+        <path>
+            <groupId>org.myorg</groupId>
+            <artifactId>custom-spi-impl</artifactId>
+            <version>${project.version}</version>
+        </path>
+    </annotationProcessorPaths>
+    <compilerArgs>
+        <arg>-Amyorg.custom.defaultNullEnumConstant=MISSING</arg>
+    </compilerArgs>
+</configuration>
+----
+====
+
+Your custom SPI implementations can then access this configured value via `MapStructProcessingEnvironment#getOptions()`.
+
+.Accessing your custom options
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+include::{processor-ap-test}/additionalsupportedoptions/UnknownEnumMappingStrategy.java[tag=documentation]
+----
+====

documentation/src/main/asciidoc/chapter-14-third-party-api-integration.asciidoc

@@ -0,0 +1,192 @@
+[[third-party-api-integration]]
+== Third-party API integration
+
+[[non-shipped-annotations]]
+=== Non-shipped annotations
+
+There are various use-cases you must resolve ambiguity for MapStruct to use a correct piece of code.
+However, the primary goal of MapStruct is to focus on bean mapping without polluting the entity code.
+For that reason, MapStruct is flexible enough to interact with already defined annotations from third-party libraries.
+The requirement to enable this behavior is to match the _name_ of such annotation.
+Hence, we say that annotation can be _from any package_.
+
+The annotations _named_ `@ConstructorProperties` and `@Default` are currently examples of this kind of annotation.
+
+[WARNING]
+====
+If such named third-party annotation exists, it does not guarantee its `@Target` matches with the intended placement.
+Be aware of placing a third-party annotation just for sake of mapping is not recommended as long as it might lead to unwanted side effects caused by that library.
+====
+
+A very common case is that no third-party dependency imported to your project provides such annotation or is inappropriate for use as already described.
+In such cases create your own annotation, for example:
+
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+package foo.support.mapstruct;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(ElementType.CONSTRUCTOR)
+@Retention(RetentionPolicy.CLASS)
+public @interface Default {
+
+}
+----
+====
+
+[[lombok]]
+=== Lombok
+
+MapStruct works together with https://projectlombok.org/[Project Lombok] as of MapStruct 1.2.0.Beta1 and Lombok 1.16.14.
+
+MapStruct takes advantage of generated getters, setters, and constructors and uses them to generate the mapper implementations.
+Be reminded that the generated code by Lombok might not always be compatible with the expectations from the individual mappings.
+In such a case, either Mapstruct mapping must be changed or Lombok must be configured accordingly using https://projectlombok.org/features/configuration[`lombok.config`] for mutual synergy.
+
+[WARNING]
+====
+Lombok 1.18.16 introduces a breaking change (https://projectlombok.org/changelog[changelog]).
+The additional annotation processor `lombok-mapstruct-binding` (https://mvnrepository.com/artifact/org.projectlombok/lombok-mapstruct-binding[Maven]) must be added otherwise MapStruct stops working with Lombok.
+This resolves the compilation issues of Lombok and MapStruct modules.
+
+[source, xml]
+----
+<path>
+    <groupId>org.projectlombok</groupId>
+    <artifactId>lombok-mapstruct-binding</artifactId>
+    <version>0.2.0</version>
+</path>
+----
+====
+
+==== Set up
+
+The set up using Maven or Gradle does not differ from what is described in <<setup>>. Additionally, you need to provide Lombok dependencies.
+
+.Maven configuration
+====
+[source, xml, linenums]
+[subs="verbatim,attributes"]
+----
+
+<properties>
+    <org.mapstruct.version>{mapstructVersion}</org.mapstruct.version>
+    <org.projectlombok.version>1.18.16</org.projectlombok.version>
+    <maven.compiler.source>1.8</maven.compiler.source>
+    <maven.compiler.target>1.8</maven.compiler.target>
+</properties>
+
+<dependencies>
+    <dependency>
+        <groupId>org.mapstruct</groupId>
+        <artifactId>mapstruct</artifactId>
+        <version>${org.mapstruct.version}</version>
+    </dependency>
+
+    <!-- lombok dependency should not end up on classpath -->
+    <dependency>
+        <groupId>org.projectlombok</groupId>
+        <artifactId>lombok</artifactId>
+        <version>${org.projectlombok.version}</version>
+        <scope>provided</scope>
+    </dependency>
+</dependencies>
+
+<build>
+    <plugins>
+        <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <version>3.8.1</version>
+            <configuration>
+                <source>1.8</source>
+                <target>1.8</target>
+                <annotationProcessorPaths>
+                    <path>
+                        <groupId>org.mapstruct</groupId>
+                        <artifactId>mapstruct-processor</artifactId>
+                        <version>${org.mapstruct.version}</version>
+                    </path>
+                    <path>
+                        <groupId>org.projectlombok</groupId>
+                        <artifactId>lombok</artifactId>
+                        <version>${org.projectlombok.version}</version>
+                    </path>
+
+                    <!-- additional annotation processor required as of Lombok 1.18.16 -->
+                    <path>
+                        <groupId>org.projectlombok</groupId>
+                        <artifactId>lombok-mapstruct-binding</artifactId>
+                        <version>0.2.0</version>
+                    </path>
+                </annotationProcessorPaths>
+            </configuration>
+        </plugin>
+    </plugins>
+</build>
+----
+====
+
+.Gradle configuration (3.4 and later)
+====
+[source, groovy, linenums]
+[subs="verbatim,attributes"]
+----
+
+dependencies {
+
+    implementation "org.mapstruct:mapstruct:${mapstructVersion}"
+    compileOnly "org.projectlombok:lombok:1.18.16"
+    annotationProcessor "org.projectlombok:lombok-mapstruct-binding:0.2.0"
+    annotationProcessor "org.mapstruct:mapstruct-processor:${mapstructVersion}"
+    annotationProcessor "org.projectlombok:lombok:1.18.16"
+}
+
+----
+====
+
+The usage combines what you already know from <<defining-mapper>> and Lombok.
+
+.Usage of MapStruct with Lombok
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Data
+public class Source {
+
+    private String test;
+}
+
+public class Target {
+
+    private Long testing;
+
+    public Long getTesting() {
+        return testing;
+    }
+
+    public void setTesting( Long testing ) {
+        this.testing = testing;
+    }
+}
+
+@Mapper
+public interface SourceTargetMapper {
+
+    SourceTargetMapper MAPPER = Mappers.getMapper( SourceTargetMapper.class );
+
+    @Mapping( source = "test", target = "testing" )
+    Target toTarget( Source s );
+}
+
+----
+====
+
+A working example can be found on the GitHub project https://github.com/mapstruct/mapstruct-examples/tree/master/mapstruct-lombok[mapstruct-lombok].

documentation/src/main/asciidoc/chapter-2-set-up.asciidoc

@@ -0,0 +1,325 @@
+[[setup]]
+== Set up
+
+MapStruct is a Java annotation processor based on http://www.jcp.org/en/jsr/detail?id=269[JSR 269] and as such can be used within command line builds (javac, Ant, Maven etc.) as well as from within your IDE.
+
+It comprises the following artifacts:
+
+* _org.mapstruct:mapstruct_: contains the required annotations such as `@Mapping`
+* _org.mapstruct:mapstruct-processor_: contains the annotation processor which generates mapper implementations
+
+=== Apache Maven
+
+For Maven based projects add the following to your POM file in order to use MapStruct:
+
+.Maven configuration
+====
+[source, xml, linenums]
+[subs="verbatim,attributes"]
+----
+...
+<properties>
+    <org.mapstruct.version>{mapstructVersion}</org.mapstruct.version>
+</properties>
+...
+<dependencies>
+    <dependency>
+        <groupId>org.mapstruct</groupId>
+        <artifactId>mapstruct</artifactId>
+        <version>${org.mapstruct.version}</version>
+    </dependency>
+</dependencies>
+...
+<build>
+    <plugins>
+        <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <version>3.8.1</version>
+            <configuration>
+                <source>1.8</source>
+                <target>1.8</target>
+                <annotationProcessorPaths>
+                    <path>
+                        <groupId>org.mapstruct</groupId>
+                        <artifactId>mapstruct-processor</artifactId>
+                        <version>${org.mapstruct.version}</version>
+                    </path>
+                </annotationProcessorPaths>
+            </configuration>
+        </plugin>
+    </plugins>
+</build>
+...
+----
+====
+
+[TIP]
+====
+If you are working with the Eclipse IDE, make sure to have a current version of the http://www.eclipse.org/m2e/[M2E plug-in].
+When importing a Maven project configured as shown above, it will set up the MapStruct annotation processor so it runs right in the IDE, whenever you save a mapper type.
+Neat, isn't it?
+
+To double check that everything is working as expected, go to your project's properties and select "Java Compiler" -> "Annotation Processing" -> "Factory Path".
+The MapStruct processor JAR should be listed and enabled there.
+Any processor options configured via the compiler plug-in (see below) should be listed under "Java Compiler" -> "Annotation Processing".
+
+If the processor is not kicking in, check that the configuration of annotation processors through M2E is enabled.
+To do so, go to "Preferences" -> "Maven" -> "Annotation Processing" and select "Automatically configure JDT APT".
+Alternatively, specify the following in the `properties` section of your POM file: `<m2e.apt.activation>jdt_apt</m2e.apt.activation>`.
+
+Also make sure that your project is using Java 1.8 or later (project properties -> "Java Compiler" -> "Compile Compliance Level").
+It will not work with older versions.
+====
+
+=== Gradle
+
+Add the following to your Gradle build file in order to enable MapStruct:
+
+.Gradle configuration
+====
+[source, groovy, linenums]
+[subs="verbatim,attributes"]
+----
+...
+plugins {
+    ...
+    id "com.diffplug.eclipse.apt" version "3.26.0" // Only for Eclipse
+}
+
+dependencies {
+    ...
+    implementation "org.mapstruct:mapstruct:${mapstructVersion}"
+    annotationProcessor "org.mapstruct:mapstruct-processor:${mapstructVersion}"
+
+    // If you are using mapstruct in test code
+    testAnnotationProcessor "org.mapstruct:mapstruct-processor:${mapstructVersion}"
+}
+...
+----
+====
+
+You can find a complete example in the https://github.com/mapstruct/mapstruct-examples/tree/master/mapstruct-on-gradle[mapstruct-examples] project on GitHub.
+
+
+=== Apache Ant
+
+Add the `javac` task configured as follows to your _build.xml_ file in order to enable MapStruct in your Ant-based project. Adjust the paths as required for your project layout.
+
+.Ant configuration
+====
+[source, xml, linenums]
+[subs="verbatim,attributes"]
+----
+...
+<javac
+    srcdir="src/main/java"
+    destdir="target/classes"
+    classpath="path/to/mapstruct-{mapstructVersion}.jar">
+    <compilerarg line="-processorpath path/to/mapstruct-processor-{mapstructVersion}.jar"/>
+    <compilerarg line="-s target/generated-sources"/>
+</javac>
+...
+----
+====
+
+You can find a complete example in the https://github.com/mapstruct/mapstruct-examples/tree/master/mapstruct-on-ant[mapstruct-examples] project on GitHub.
+
+[[configuration-options]]
+=== Configuration options
+
+The MapStruct code generator can be configured using _annotation processor options_.
+
+When invoking javac directly, these options are passed to the compiler in the form _-Akey=value_. When using MapStruct via Maven, any processor options can be passed using `compilerArgs` within the configuration of the Maven processor plug-in like this:
+
+.Maven configuration
+====
+[source, xml, linenums]
+[subs="verbatim,attributes"]
+----
+...
+<plugin>
+    <groupId>org.apache.maven.plugins</groupId>
+    <artifactId>maven-compiler-plugin</artifactId>
+    <version>3.5.1</version>
+    <configuration>
+        <source>1.8</source>
+        <target>1.8</target>
+        <annotationProcessorPaths>
+            <path>
+                <groupId>org.mapstruct</groupId>
+                <artifactId>mapstruct-processor</artifactId>
+                <version>${org.mapstruct.version}</version>
+            </path>
+        </annotationProcessorPaths>
+        <!-- due to problem in maven-compiler-plugin, for verbose mode add showWarnings -->
+        <showWarnings>true</showWarnings>
+        <compilerArgs>
+            <arg>
+                -Amapstruct.suppressGeneratorTimestamp=true
+            </arg>
+            <arg>
+                -Amapstruct.suppressGeneratorVersionInfoComment=true
+            </arg>
+            <arg>
+                -Amapstruct.verbose=true
+            </arg>
+        </compilerArgs>
+    </configuration>
+</plugin>
+...
+----
+====
+
+.Gradle configuration
+====
+[source, groovy, linenums]
+[subs="verbatim,attributes"]
+----
+...
+compileJava {
+    options.compilerArgs += [
+        '-Amapstruct.suppressGeneratorTimestamp=true',
+        '-Amapstruct.suppressGeneratorVersionInfoComment=true',
+        '-Amapstruct.verbose=true'
+    ]
+}
+...
+----
+====
+
+The following options exist:
+
+.MapStruct processor options
+[cols="1,2a,1"]
+|===
+|Option|Purpose|Default
+
+|`mapstruct.
+suppressGeneratorTimestamp`
+|If set to `true`, the creation of a time stamp in the `@Generated` annotation in the generated mapper classes is suppressed.
+|`false`
+
+|`mapstruct.verbose`
+|If set to `true`, MapStruct in which MapStruct logs its major decisions. Note, at the moment of writing in Maven, also `showWarnings` needs to be added due to a problem in the maven-compiler-plugin configuration.
+|`false`
+
+|`mapstruct.
+suppressGeneratorVersionInfoComment`
+|If set to `true`, the creation of the `comment` attribute in the `@Generated` annotation in the generated mapper classes is suppressed. The comment contains information about the version of MapStruct and about the compiler used for the annotation processing.
+|`false`
+
+|`mapstruct.defaultComponentModel`
+|The name of the component model (see <<retrieving-mapper>>) based on which mappers should be generated.
+
+Supported values are:
+
+* `default`: the mapper uses no component model, instances are typically retrieved via `Mappers#getMapper(Class)`
+* `cdi`: the generated mapper is an application-scoped (from javax.enterprise.context or jakarta.enterprise.context, depending on which one is available with javax.inject having priority) CDI bean and can be retrieved via `@Inject`
+* `spring`: the generated mapper is a singleton-scoped Spring bean and can be retrieved via `@Autowired`
+* `jsr330`: the generated mapper is annotated with {@code @Named} and can be retrieved via `@Inject` (from javax.inject or jakarta.inject, depending which one is available with javax.inject having priority), e.g. using Spring
+* `jakarta`: the generated mapper is annotated with {@code @Named} and can be retrieved via `@Inject` (from jakarta.inject), e.g. using Spring
+* `jakarta-cdi`: the generated mapper is an application-scoped (from jakarta.enterprise.context) CDI bean and can be retrieved via `@Inject`
+
+If a component model is given for a specific mapper via `@Mapper#componentModel()`, the value from the annotation takes precedence.
+|`default`
+
+|`mapstruct.defaultInjectionStrategy`
+| The type of the injection in mapper via parameter `uses`. This is only used on annotated based component models
+  such as CDI, Spring and JSR 330.
+
+Supported values are:
+
+* `field`: dependencies will be injected in fields
+* `constructor`: will be generated constructor. Dependencies will be injected via constructor.
+
+When CDI `componentModel` a default constructor will also be generated.
+If a injection strategy is given for a specific mapper via `@Mapper#injectionStrategy()`, the value from the annotation takes precedence over the option.
+|`field`
+
+|`mapstruct.unmappedTargetPolicy`
+|The default reporting policy to be applied in case an attribute of the target object of a mapping method is not populated with a source value.
+
+Supported values are:
+
+* `ERROR`: any unmapped target property will cause the mapping code generation to fail
+* `WARN`: any unmapped target property will cause a warning at build time
+* `IGNORE`: unmapped target properties are ignored
+
+If a policy is given for a specific mapper via `@Mapper#unmappedTargetPolicy()`, the value from the annotation takes precedence.
+If a policy is given for a specific bean mapping via `@BeanMapping#unmappedTargetPolicy()`, it takes precedence over both `@Mapper#unmappedTargetPolicy()` and the option.
+|`WARN`
+
+|`mapstruct.unmappedSourcePolicy`
+|The default reporting policy to be applied in case an attribute of the source object of a mapping method is not populated with a target value.
+
+Supported values are:
+
+* `ERROR`: any unmapped source property will cause the mapping code generation to fail
+* `WARN`: any unmapped source property will cause a warning at build time
+* `IGNORE`: unmapped source properties are ignored
+
+If a policy is given for a specific mapper via `@Mapper#unmappedSourcePolicy()`, the value from the annotation takes precedence.
+If a policy is given for a specific bean mapping via `@BeanMapping#ignoreUnmappedSourceProperties()`, it takes precedence over both `@Mapper#unmappedSourcePolicy()` and the option.
+|`IGNORE`
+
+|`mapstruct.
+disableBuilders`
+|If set to `true`, then MapStruct will not use builder patterns when doing the mapping. This is equivalent to doing `@Mapper( builder = @Builder( disableBuilder = true ) )` for all of your mappers.
+|`false`
+
+|`mapstruct.nullValueIterableMappingStrategy`
+|The strategy to be applied when `null` is passed as a source value to an iterable mapping.
+
+Supported values are:
+
+* `RETURN_NULL`: if `null` is passed as a source value, then `null` will be returned
+* `RETURN_DEFAULT`: if `null` is passed then a default value (empty collection) will be returned
+
+If a strategy is given for a specific mapper via `@Mapper#nullValueIterableMappingStrategy()`, the value from the annotation takes precedence.
+If a strategy is given for a specific iterable mapping via `@IterableMapping#nullValueMappingStrategy()`, it takes precedence over both `@Mapper#nullValueIterableMappingStrategy()` and the option.
+|`RETURN_NULL`
+
+|`mapstruct.nullValueMapMappingStrategy`
+|The strategy to be applied when `null` is passed as a source value to a map mapping.
+
+Supported values are:
+
+* `RETURN_NULL`: if `null` is passed as a source value, then `null` will be returned
+* `RETURN_DEFAULT`: if `null` is passed then a default value (empty map) will be returned
+
+If a strategy is given for a specific mapper via `@Mapper#nullValueMapMappingStrategy()`, the value from the annotation takes precedence.
+If a strategy is given for a specific map mapping via `@MapMapping#nullValueMappingStrategy()`, it takes precedence over both `@Mapper#nullValueMapMappingStrategy()` and the option.
+|`RETURN_NULL`
+|===
+
+=== Using MapStruct with the Java Module System
+
+MapStruct can be used with Java 9 and higher versions.
+
+To allow usage of the `@Generated` annotation `java.annotation.processing.Generated` (part of the `java.compiler` module) can be enabled.
+
+=== IDE Integration
+
+There are optional MapStruct plugins for IntelliJ and Eclipse that allow you to have additional completion support (and more) in the annotations.
+
+==== IntelliJ
+
+The https://plugins.jetbrains.com/plugin/10036-mapstruct-support[MapStruct IntelliJ] plugin offers assistance in projects that use MapStruct.
+
+Some features include:
+
+* Code completion in `target`, `source`, `expression`
+* Go To Declaration for properties in `target` and `source`
+* Find Usages of properties in `target` and `source`
+* Refactoring support
+* Errors and Quick Fixes
+
+==== Eclipse
+
+The https://marketplace.eclipse.org/content/mapstruct-eclipse-plugin[MapStruct Eclipse] Plugin offers assistance in projects that use MapStruct.
+
+Some features include:
+
+* Code completion in `target` and `source`
+* Quick Fixes

documentation/src/main/asciidoc/chapter-3-defining-a-mapper.asciidoc

@@ -0,0 +1,866 @@
+[[defining-mapper]]
+== Defining a mapper
+
+In this section you'll learn how to define a bean mapper with MapStruct and which options you have to do so.
+
+[[basic-mappings]]
+=== Basic mappings
+
+To create a mapper simply define a Java interface with the required mapping method(s) and annotate it with the `org.mapstruct.Mapper` annotation:
+
+.Java interface to define a mapper
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    @Mapping(target = "manufacturer", source = "make")
+    @Mapping(target = "seatCount", source = "numberOfSeats")
+    CarDto carToCarDto(Car car);
+
+    @Mapping(target = "fullName", source = "name")
+    PersonDto personToPersonDto(Person person);
+}
+----
+====
+
+The `@Mapper` annotation causes the MapStruct code generator to create an implementation of the `CarMapper` interface during build-time.
+
+In the generated method implementations all readable properties from the source type (e.g. `Car`) will be copied into the corresponding property in the target type (e.g. `CarDto`):
+
+* When a property has the same name as its target entity counterpart, it will be mapped implicitly.
+* When a property has a different name in the target entity, its name can be specified via the `@Mapping` annotation.
+
+[TIP]
+====
+The property name as defined in the http://www.oracle.com/technetwork/java/javase/documentation/spec-136004.html[JavaBeans specification] must be specified in the `@Mapping` annotation, e.g. _seatCount_ for a property with the accessor methods `getSeatCount()` and `setSeatCount()`.
+====
+[TIP]
+====
+By means of the `@BeanMapping(ignoreByDefault = true)` the default behavior will be *explicit mapping*, meaning that all mappings (including nested ones) have to be specified by means of the `@Mapping` and no warnings will be issued on missing target properties.
+This allows to ignore all fields, except the ones that are explicitly defined through `@Mapping`.
+====
+[TIP]
+====
+Fluent setters are also supported.
+Fluent setters are setters that return the same type as the type being modified.
+
+E.g.
+
+```
+public Builder seatCount(int seatCount) {
+    this.seatCount = seatCount;
+    return this;
+}
+```
+====
+
+
+To get a better understanding of what MapStruct does have a look at the following implementation of the `carToCarDto()` method as generated by MapStruct:
+
+.Code generated by MapStruct
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class CarMapperImpl implements CarMapper {
+
+    @Override
+    public CarDto carToCarDto(Car car) {
+        if ( car == null ) {
+            return null;
+        }
+
+        CarDto carDto = new CarDto();
+
+        if ( car.getFeatures() != null ) {
+            carDto.setFeatures( new ArrayList<String>( car.getFeatures() ) );
+        }
+        carDto.setManufacturer( car.getMake() );
+        carDto.setSeatCount( car.getNumberOfSeats() );
+        carDto.setDriver( personToPersonDto( car.getDriver() ) );
+        carDto.setPrice( String.valueOf( car.getPrice() ) );
+        if ( car.getCategory() != null ) {
+            carDto.setCategory( car.getCategory().toString() );
+        }
+        carDto.setEngine( engineToEngineDto( car.getEngine() ) );
+
+        return carDto;
+    }
+
+    @Override
+    public PersonDto personToPersonDto(Person person) {
+        //...
+    }
+
+    private EngineDto engineToEngineDto(Engine engine) {
+        if ( engine == null ) {
+            return null;
+        }
+
+        EngineDto engineDto = new EngineDto();
+
+        engineDto.setHorsePower(engine.getHorsePower());
+        engineDto.setFuel(engine.getFuel());
+
+        return engineDto;
+    }
+}
+----
+====
+
+The general philosophy of MapStruct is to generate code which looks as much as possible as if you had written it yourself from hand. In particular this means that the values are copied from source to target by plain getter/setter invocations instead of reflection or similar.
+
+As the example shows the generated code takes into account any name mappings specified via `@Mapping`.
+If the type of a mapped attribute is different in source and target entity,
+MapStruct will either apply an automatic conversion (as e.g. for the _price_ property, see also <<implicit-type-conversions>>)
+or optionally invoke / create another mapping method (as e.g. for the _driver_ / _engine_ property, see also <<mapping-object-references>>).
+MapStruct will only create a new mapping method if and only if the source and target property are properties of a Bean and they themselves are Beans or simple properties.
+i.e. they are not `Collection` or `Map` type properties.
+
+Collection-typed attributes with the same element type will be copied by creating a new instance of the target collection type containing the elements from the source property. For collection-typed attributes with different element types each element will be mapped individually and added to the target collection (see <<mapping-collections>>).
+
+MapStruct takes all public properties of the source and target types into account. This includes properties declared on super-types.
+
+[[mapping-composition]]
+=== Mapping Composition
+MapStruct supports the use of meta annotations. The `@Mapping` annotation supports now `@Target` with `ElementType#ANNOTATION_TYPE` in addition to `ElementType#METHOD`. This allows `@Mapping` to be used on other (user defined) annotations for re-use purposes. For example:
+
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Retention(RetentionPolicy.CLASS)
+@Mapping(target = "id", ignore = true)
+@Mapping(target = "creationDate", expression = "java(new java.util.Date())")
+@Mapping(target = "name", source = "groupName")
+public @interface ToEntity { }
+----
+====
+
+Can be used to characterise an `Entity` without the need to have a common base type. For instance, `ShelveEntity` and `BoxEntity` do not share a common base type in the `StorageMapper` below.
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface StorageMapper {
+
+    StorageMapper INSTANCE = Mappers.getMapper( StorageMapper.class );
+
+    @ToEntity
+    @Mapping( target = "weightLimit", source = "maxWeight")
+    ShelveEntity map(ShelveDto source);
+
+    @ToEntity
+    @Mapping( target = "label", source = "designation")
+    BoxEntity map(BoxDto source);
+}
+----
+====
+
+Still, they do have some properties in common. The `@ToEntity` assumes both target beans `ShelveEntity` and `BoxEntity` have properties: `"id"`, `"creationDate"` and `"name"`. It furthermore assumes that the source beans `ShelveDto` and `BoxDto` always have a property `"groupName"`. This concept is also known as "duck-typing". In other words, if it quacks like duck, walks like a duck its probably a duck.
+
+Error messages are not mature yet: the method on which the problem occurs is displayed, as well as the concerned values in the `@Mapping` annotation. However, the composition aspect is not visible. The messages are "as if" the `@Mapping` would be present on the concerned method directly.
+Therefore, the user should use this feature with care, especially when uncertain when a property is always present.
+
+A more typesafe (but also more verbose) way would be to define base classes / interfaces on the target bean and the source bean and use `@InheritConfiguration` to achieve the same result (see <<mapping-configuration-inheritance>>).
+
+[[adding-custom-methods]]
+=== Adding custom methods to mappers
+
+In some cases it can be required to manually implement a specific mapping from one type to another which can't be generated by MapStruct. One way to handle this is to implement the custom method on another class which then is used by mappers generated by MapStruct (see <<invoking-other-mappers>>).
+
+Alternatively, when using Java 8 or later, you can implement custom methods directly in a mapper interface as default methods. The generated code will invoke the default methods if the argument and return types match.
+
+As an example let's assume the mapping from `Person` to `PersonDto` requires some special logic which can't be generated by MapStruct. You could then define the mapper from the previous example like this:
+
+.Mapper which defines a custom mapping with a default method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    @Mapping(...)
+    ...
+    CarDto carToCarDto(Car car);
+
+    default PersonDto personToPersonDto(Person person) {
+        //hand-written mapping logic
+    }
+}
+----
+====
+
+The class generated by MapStruct implements the method `carToCarDto()`. The generated code in `carToCarDto()` will invoke the manually implemented `personToPersonDto()` method when mapping the `driver` attribute.
+
+A mapper could also be defined in the form of an abstract class instead of an interface and implement the custom methods directly in the mapper class. In this case MapStruct will generate an extension of the abstract class with implementations of all abstract methods. An advantage of this approach over declaring default methods is that additional fields could be declared in the mapper class.
+
+The previous example where the mapping from `Person` to `PersonDto` requires some special logic could then be defined like this:
+
+.Mapper defined by an abstract class
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public abstract class CarMapper {
+
+    @Mapping(...)
+    ...
+    public abstract CarDto carToCarDto(Car car);
+
+    public PersonDto personToPersonDto(Person person) {
+        //hand-written mapping logic
+    }
+}
+----
+====
+
+MapStruct will generate a sub-class of `CarMapper` with an implementation of the `carToCarDto()` method as it is declared abstract. The generated code in `carToCarDto()` will invoke the manually implemented `personToPersonDto()` method when mapping the `driver` attribute.
+
+[[mappings-with-several-source-parameters]]
+=== Mapping methods with several source parameters
+
+MapStruct also supports mapping methods with several source parameters. This is useful e.g. in order to combine several entities into one data transfer object. The following shows an example:
+
+.Mapping method with several source parameters
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface AddressMapper {
+
+    @Mapping(target = "description", source = "person.description")
+    @Mapping(target = "houseNumber", source = "address.houseNo")
+    DeliveryAddressDto personAndAddressToDeliveryAddressDto(Person person, Address address);
+}
+----
+====
+
+The shown mapping method takes two source parameters and returns a combined target object. As with single-parameter mapping methods properties are mapped by name.
+
+In case several source objects define a property with the same name, the source parameter from which to retrieve the property must be specified using the `@Mapping` annotation as shown for the `description` property in the example. An error will be raised when such an ambiguity is not resolved. For properties which only exist once in the given source objects it is optional to specify the source parameter's name as it can be determined automatically.
+
+[WARNING]
+====
+Specifying the parameter in which the property resides is mandatory when using the `@Mapping` annotation.
+====
+
+[TIP]
+====
+Mapping methods with several source parameters will return `null` in case all the source parameters are `null`. Otherwise the target object will be instantiated and all properties from the provided parameters will be propagated.
+====
+
+MapStruct also offers the possibility to directly refer to a source parameter.
+
+.Mapping method directly referring to a source parameter
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface AddressMapper {
+
+    @Mapping(target = "description", source = "person.description")
+    @Mapping(target = "houseNumber", source = "hn")
+    DeliveryAddressDto personAndAddressToDeliveryAddressDto(Person person, Integer hn);
+}
+----
+====
+
+In this case the source parameter is directly mapped into the target as the example above demonstrates. The parameter `hn`, a non bean type (in this case `java.lang.Integer`) is mapped to `houseNumber`.
+
+[[mapping-nested-bean-properties-to-current-target]]
+=== Mapping nested bean properties to current target
+
+If you don't want explicitly name all properties from nested source bean, you can use `.` as target.
+ This will tell MapStruct to map every property from source bean to target object. The following shows an example:
+
+.use of "target this" annotation "."
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+ @Mapper
+ public interface CustomerMapper {
+
+     @Mapping( target = "name", source = "record.name" )
+     @Mapping( target = ".", source = "record" )
+     @Mapping( target = ".", source = "account" )
+     Customer customerDtoToCustomer(CustomerDto customerDto);
+ }
+----
+====
+
+The generated code will map every property from `CustomerDto.record` to `Customer` directly, without need to manually name any of them.
+The same goes for `Customer.account`.
+
+When there are conflicts, these can be resolved by explicitly defining the mapping. For instance in the example above. `name` occurs in `CustomerDto.record` and in `CustomerDto.account`. The mapping `@Mapping( target = "name", source = "record.name" )` resolves this conflict.
+
+
+This "target this" notation can be very useful when mapping hierarchical objects to flat objects and vice versa (`@InheritInverseConfiguration`).
+
+
+
+[[updating-bean-instances]]
+=== Updating existing bean instances
+
+In some cases you need mappings which don't create a new instance of the target type but instead update an existing instance of that type. This sort of mapping can be realized by adding a parameter for the target object and marking this parameter with `@MappingTarget`. The following shows an example:
+
+.Update method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    void updateCarFromDto(CarDto carDto, @MappingTarget Car car);
+}
+----
+====
+
+The generated code of the `updateCarFromDto()` method will update the passed `Car` instance with the properties from the given `CarDto` object. There may be only one parameter marked as mapping target. Instead of `void` you may also set the method's return type to the type of the target parameter, which will cause the generated implementation to update the passed mapping target and return it as well. This allows for fluent invocations of mapping methods.
+
+For `CollectionMappingStrategy.ACCESSOR_ONLY` Collection- or map-typed properties of the target bean to be updated will be cleared and then populated with the values from the corresponding source collection or map. Otherwise, For `CollectionMappingStrategy.ADDER_PREFERRED` or `CollectionMappingStrategy.TARGET_IMMUTABLE` the target will not be cleared and the values will be populated immediately.
+
+[[direct-field-mappings]]
+=== Mappings with direct field access
+
+MapStruct also supports mappings of `public` fields that have no getters/setters. MapStruct will
+use the fields as read/write accessor if it cannot find suitable getter/setter methods for the property.
+
+A field is considered as a read accessor if it is `public` or `public final`. If a field is `static` it is not
+considered as a read accessor.
+
+A field is considered as a write accessor only if it is `public`. If a field is `final` and/or `static` it is not
+considered as a write accessor.
+
+Small example:
+
+.Example classes for mapping
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class Customer {
+
+    private Long id;
+    private String name;
+
+    //getters and setter omitted for brevity
+}
+
+public class CustomerDto {
+
+    public Long id;
+    public String customerName;
+}
+
+@Mapper
+public interface CustomerMapper {
+
+    CustomerMapper INSTANCE = Mappers.getMapper( CustomerMapper.class );
+
+    @Mapping(target = "name", source = "customerName")
+    Customer toCustomer(CustomerDto customerDto);
+
+    @InheritInverseConfiguration
+    CustomerDto fromCustomer(Customer customer);
+}
+----
+====
+
+For the configuration from above, the generated mapper looks like:
+
+.Generated mapper for example classes
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class CustomerMapperImpl implements CustomerMapper {
+
+    @Override
+    public Customer toCustomer(CustomerDto customerDto) {
+        // ...
+        customer.setId( customerDto.id );
+        customer.setName( customerDto.customerName );
+        // ...
+    }
+
+    @Override
+    public CustomerDto fromCustomer(Customer customer) {
+        // ...
+        customerDto.id = customer.getId();
+        customerDto.customerName = customer.getName();
+        // ...
+    }
+}
+----
+====
+
+You can find the complete example in the
+https://github.com/mapstruct/mapstruct-examples/tree/master/mapstruct-field-mapping[mapstruct-examples-field-mapping]
+project on GitHub.
+
+[[mapping-with-builders]]
+=== Using builders
+
+MapStruct also supports mapping of immutable types via builders.
+When performing a mapping MapStruct checks if there is a builder for the type being mapped.
+This is done via the `BuilderProvider` SPI.
+If a Builder exists for a certain type, then that builder will be used for the mappings.
+
+The default implementation of the `BuilderProvider` assumes the following:
+
+* The type has either
+** A parameterless public static builder creation method that returns a builder.
+e.g. `Person` has a public static method that returns `PersonBuilder`.
+** A public static inner class with the name having the suffix "Builder", and a public no-args constructor
+e.g. `Person` has an inner class `PersonBuilder` with a public no-args constructor.
+* The builder type has a parameterless public method (build method) that returns the type being built.
+In our example `PersonBuilder` has a method returning `Person`.
+* In case there are multiple build methods, MapStruct will look for a method called `build`, if such method exists
+then this would be used, otherwise a compilation error would be created.
+* A specific build method can be defined by using `@Builder` within: `@BeanMapping`, `@Mapper` or `@MapperConfig`
+* In case there are multiple builder creation methods that satisfy the above conditions then a `MoreThanOneBuilderCreationMethodException`
+will be thrown from the `DefaultBuilderProvider` SPI.
+In case of a `MoreThanOneBuilderCreationMethodException` MapStruct will write a warning in the compilation and not use any builder.
+
+If such type is found then MapStruct will use that type to perform the mapping to (i.e. it will look for setters into that type).
+To finish the mapping MapStruct generates code that will invoke the build method of the builder.
+
+[NOTE]
+======
+Builder detection can be switched off by means of `@Builder#disableBuilder`. MapStruct will fall back on regular getters / setters in case builders are disabled.
+======
+
+[NOTE]
+======
+The <<object-factories>> are also considered for the builder type.
+E.g. If an object factory exists for our `PersonBuilder` then this factory would be used instead of the builder creation method.
+======
+
+[NOTE]
+======
+Detected builders influence `@BeforeMapping` and `@AfterMapping` behavior. See <<customizing-mappings-with-before-and-after>> for more information.
+======
+
+.Person with Builder example
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class Person {
+
+    private final String name;
+
+    protected Person(Person.Builder builder) {
+        this.name = builder.name;
+    }
+
+    public static Person.Builder builder() {
+        return new Person.Builder();
+    }
+
+    public static class Builder {
+
+        private String name;
+
+        public Builder name(String name) {
+            this.name = name;
+            return this;
+        }
+
+        public Person create() {
+            return new Person( this );
+        }
+    }
+}
+----
+====
+
+.Person Mapper definition
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public interface PersonMapper {
+
+    Person map(PersonDto dto);
+}
+----
+====
+
+.Generated mapper with builder
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class PersonMapperImpl implements PersonMapper {
+
+    public Person map(PersonDto dto) {
+        if (dto == null) {
+            return null;
+        }
+
+        Person.Builder builder = Person.builder();
+
+        builder.name( dto.getName() );
+
+        return builder.create();
+    }
+}
+----
+====
+
+Supported builder frameworks:
+
+* https://projectlombok.org/[Lombok] - It is required to have the Lombok classes in a separate module.
+See for more information at https://github.com/rzwitserloot/lombok/issues/1538[rzwitserloot/lombok#1538] and to set up Lombok with MapStruct, refer to <<lombok>>.
+* https://github.com/google/auto/blob/master/value/userguide/index.md[AutoValue]
+* https://immutables.github.io/[Immutables] - When Immutables are present on the annotation processor path then the `ImmutablesAccessorNamingStrategy` and `ImmutablesBuilderProvider` would be used by default
+* https://github.com/google/FreeBuilder[FreeBuilder] - When FreeBuilder is present on the annotation processor path then the `FreeBuilderAccessorNamingStrategy` would be used by default.
+When using FreeBuilder then the JavaBean convention should be followed, otherwise MapStruct won't recognize the fluent getters.
+* It also works for custom builders (handwritten ones) if the implementation supports the defined rules for the default `BuilderProvider`.
+Otherwise, you would need to write a custom `BuilderProvider`
+
+[TIP]
+====
+In case you want to disable using builders then you can pass the MapStruct processor option `mapstruct.disableBuilders` to the compiler. e.g. `-Amapstruct.disableBuilders=true`.
+====
+
+[[mapping-with-constructors]]
+=== Using Constructors
+
+MapStruct supports using constructors for mapping target types.
+When doing a mapping MapStruct checks if there is a builder for the type being mapped.
+If there is no builder, then MapStruct looks for a single accessible constructor.
+When there are multiple constructors then the following is done to pick the one which should be used:
+
+* If a constructor is annotated with an annotation _named_ `@Default` (from any package, see <<non-shipped-annotations>>) it will be used.
+* If a single public constructor exists then it will be used to construct the object, and the other non public constructors will be ignored.
+* If a parameterless constructor exists then it will be used to construct the object, and the other constructors will be ignored.
+* If there are multiple eligible constructors then there will be a compilation error due to ambiguous constructors. In order to break the ambiguity an annotation _named_ `@Default` (from any package, see <<non-shipped-annotations>>) can used.
+
+.Deciding which constructor to use
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class Vehicle {
+
+    protected Vehicle() { }
+
+    // MapStruct will use this constructor, because it is a single public constructor
+    public Vehicle(String color) { }
+}
+
+public class Car {
+
+    // MapStruct will use this constructor, because it is a parameterless empty constructor
+    public Car() { }
+
+    public Car(String make, String color) { }
+}
+
+public class Truck {
+
+    public Truck() { }
+
+    // MapStruct will use this constructor, because it is annotated with @Default
+    @Default
+    public Truck(String make, String color) { }
+}
+
+public class Van {
+
+    // There will be a compilation error when using this class because MapStruct cannot pick a constructor
+
+    public Van(String make) { }
+
+    public Van(String make, String color) { }
+
+}
+----
+====
+
+When using a constructor then the names of the parameters of the constructor will be used and matched to the target properties.
+When the constructor has an annotation _named_ `@ConstructorProperties` (from any package, see <<non-shipped-annotations>>) then this annotation will be used to get the names of the parameters.
+
+[NOTE]
+====
+When an object factory method or a method annotated with `@ObjectFactory` exists, it will take precedence over any constructor defined in the target.
+The target object constructor will not be used in that case.
+====
+
+
+.Person with constructor parameters
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class Person {
+
+    private final String name;
+    private final String surname;
+
+    public Person(String name, String surname) {
+        this.name = name;
+        this.surname = surname;
+    }
+}
+----
+====
+
+.Person With Constructor Mapper definition
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public interface PersonMapper {
+
+    Person map(PersonDto dto);
+}
+----
+====
+
+.Generated mapper with constructor
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class PersonMapperImpl implements PersonMapper {
+
+    public Person map(PersonDto dto) {
+        if (dto == null) {
+            return null;
+        }
+
+        String name;
+        String surname;
+        name = dto.getName();
+        surname = dto.getSurname();
+
+        Person person = new Person( name, surname );
+
+        return person;
+    }
+}
+----
+====
+
+[[mapping-map-to-bean]]
+=== Mapping Map to Bean
+
+There are situations when a mapping from a `Map<String, ???>` into a specific bean is needed.
+MapStruct offers a transparent way of doing such a mapping by using the target bean properties (or defined through `Mapping#source`) to extract the values from the map.
+Such a mapping looks like:
+
+.Example classes for mapping map to bean
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class Customer {
+
+    private Long id;
+    private String name;
+
+    //getters and setter omitted for brevity
+}
+
+@Mapper
+public interface CustomerMapper {
+
+    @Mapping(target = "name", source = "customerName")
+    Customer toCustomer(Map<String, String> map);
+
+}
+----
+====
+
+.Generated mapper for mapping map to bean
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class CustomerMapperImpl implements CustomerMapper {
+
+    @Override
+    public Customer toCustomer(Map<String, String> map) {
+        // ...
+        if ( map.containsKey( "id" ) ) {
+            customer.setId( Integer.parseInt( map.get( "id" ) ) );
+        }
+        if ( map.containsKey( "customerName" ) ) {
+            customer.setName( map.get( "customerName" ) );
+        }
+        // ...
+    }
+}
+----
+====
+
+[NOTE]
+====
+All existing rules about mapping between different types and using other mappers defined with `Mapper#uses` or custom methods in the mappers are applied.
+i.e. You can map from `Map<String, Integer>` where for each property a conversion from `Integer` into the respective property will be needed.
+====
+
+[WARNING]
+====
+When a raw map or a map that does not have a String as a key is used, then a warning will be generated.
+The warning is not generated if the map itself is mapped into some other target property directly as is.
+====
+
+[[adding-annotations]]
+=== Adding annotations
+
+Other frameworks sometimes requires you to add annotations to certain classes so that they can easily detect the mappers.
+Using the `@AnnotateWith` annotation you can generate an annotation at the specified location.
+
+For example Apache Camel has a `@Converter` annotation which you can apply to generated mappers using the `@AnnotateWith` annotation.
+
+.AnnotateWith source example
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+@AnnotateWith(
+  value = Converter.class,
+  elements = @AnnotateWith.Element( name = "generateBulkLoader", booleans = true )
+)
+public interface MyConverter {
+    @AnnotateWith( Converter.class )
+    DomainObject map( DtoObject dto );
+}
+----
+====
+
+.AnnotateWith generated mapper
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Converter( generateBulkLoader = true )
+public class MyConverterImpl implements MyConverter {
+    @Converter
+    public DomainObject map( DtoObject dto ) {
+        // default mapping behaviour
+    }
+}
+----
+====
+
+
+[[javadoc]]
+=== Adding Javadoc comments
+
+MapStruct provides support for defining Javadoc comments in the generated mapper implementation using the
+`org.mapstruct.Javadoc` annotation.
+
+This functionality could be relevant especially in situations where certain Javadoc standards need to be met or
+to deal with Javadoc validation constraints.
+
+The `@Javadoc` annotation defines attributes for the different Javadoc elements.
+
+Consider the following example:
+
+.Javadoc annotation example
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+@Javadoc(
+    value = "This is the description",
+    authors = { "author1", "author2" },
+    deprecated = "Use {@link OtherMapper} instead",
+    since = "0.1"
+)
+public interface MyAnnotatedWithJavadocMapper {
+    //...
+}
+----
+====
+
+.Javadoc annotated generated mapper
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+/**
+* This is the description
+*
+* @author author1
+* @author author2
+*
+* @deprecated Use {@link OtherMapper} instead
+* @since 0.1
+*/
+public class MyAnnotatedWithJavadocMapperImpl implements MyAnnotatedWithJavadocMapper {
+    //...
+}
+----
+====
+
+The entire Javadoc comment block can be provided directly as well.
+
+.Javadoc annotation example with the entire Javadoc comment block provided directly
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+@Javadoc(
+    "This is the description\n"
+  + "\n"
+  + "@author author1\n"
+  + "@author author2\n"
+  + "\n"
+  + "@deprecated Use {@link OtherMapper} instead\n"
+  + "@since 0.1\n"
+)
+public interface MyAnnotatedWithJavadocMapper {
+    //...
+}
+----
+====
+
+Or using Text blocks:
+
+.Javadoc annotation example with the entire Javadoc comment block provided directly using Text blocks
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+@Javadoc(
+    """
+    This is the description
+
+    @author author1
+    @author author2
+
+    @deprecated Use {@link OtherMapper} instead
+    @since 0.1
+    """
+)
+public interface MyAnnotatedWithJavadocMapper {
+    //...
+}
+----
+====

documentation/src/main/asciidoc/chapter-4-retrieving-a-mapper.asciidoc

@@ -0,0 +1,133 @@
+[[retrieving-mapper]]
+== Retrieving a mapper
+
+[[mappers-factory]]
+=== The Mappers factory (no dependency injection)
+
+When not using a DI framework, Mapper instances can be retrieved via the `org.mapstruct.factory.Mappers` class. Just invoke the `getMapper()` method, passing the interface type of the mapper to return:
+
+.Using the Mappers factory
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+CarMapper mapper = Mappers.getMapper( CarMapper.class );
+----
+====
+
+By convention, a mapper interface should define a member called `INSTANCE` which holds a single instance of the mapper type:
+
+.Declaring an instance of a mapper (interface)
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    CarMapper INSTANCE = Mappers.getMapper( CarMapper.class );
+
+    CarDto carToCarDto(Car car);
+}
+
+----
+====
+
+.Declaring an instance of a mapper (abstract class)
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public abstract class CarMapper {
+
+    public static final CarMapper INSTANCE = Mappers.getMapper( CarMapper.class );
+
+    CarDto carToCarDto(Car car);
+}
+
+----
+====
+
+This pattern makes it very easy for clients to use mapper objects without repeatedly instantiating new instances:
+
+.Accessing a mapper
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+Car car = ...;
+CarDto dto = CarMapper.INSTANCE.carToCarDto( car );
+----
+====
+
+
+Note that mappers generated by MapStruct are stateless and thread-safe and thus can safely be accessed from several threads at the same time.
+
+[[using-dependency-injection]]
+=== Using dependency injection
+
+If you're working with a dependency injection framework such as http://jcp.org/en/jsr/detail?id=346[CDI] (Contexts and Dependency Injection for Java^TM^ EE) or the http://www.springsource.org/spring-framework[Spring Framework], it is recommended to obtain mapper objects via dependency injection and *not* via the `Mappers` class as described above. For that purpose you can specify the component model which generated mapper classes should be based on either via `@Mapper#componentModel` or using a processor option as described in <<configuration-options>>.
+
+Currently there is support for CDI and Spring (the latter either via its custom annotations or using the JSR 330 annotations). See <<configuration-options>> for the allowed values of the `componentModel` attribute which are the same as for the `mapstruct.defaultComponentModel` processor option and constants are defined in a class `MappingConstants.ComponentModel`.  In both cases the required annotations will be added to the generated mapper implementations classes in order to make the same subject to dependency injection. The following shows an example using CDI:
+
+.A mapper using the CDI component model
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper(componentModel = MappingConstants.ComponentModel.CDI)
+public interface CarMapper {
+
+    CarDto carToCarDto(Car car);
+}
+
+----
+====
+
+The generated mapper implementation will be marked with the `@ApplicationScoped` annotation and thus can be injected into fields, constructor arguments etc. using the `@Inject` annotation:
+
+.Obtaining a mapper via dependency injection
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Inject
+private CarMapper mapper;
+----
+====
+
+A mapper which uses other mapper classes (see <<invoking-other-mappers>>) will obtain these mappers using the configured component model. So if `CarMapper` from the previous example was using another mapper, this other mapper would have to be an injectable CDI bean as well.
+
+[[injection-strategy]]
+=== Injection strategy
+
+When using <<using-dependency-injection,dependency injection>>, you can choose between constructor, field, or setter injection.
+This can be done by either providing the injection strategy via `@Mapper` or `@MapperConfig` annotation.
+
+.Using constructor injection
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper(componentModel = MappingConstants.ComponentModel.CDI, uses = EngineMapper.class, injectionStrategy = InjectionStrategy.CONSTRUCTOR)
+public interface CarMapper {
+    CarDto carToCarDto(Car car);
+}
+----
+====
+
+The generated mapper will inject classes defined in the **uses** attribute if MapStruct has detected that it needs to use an instance of it for a mapping.
+When `InjectionStrategy#CONSTRUCTOR` is used, the constructor will have the appropriate annotation and the fields won't.
+When `InjectionStrategy#FIELD` is used, the annotation is on the field itself.
+When `InjectionStrategy#SETTER` is used the annotation is on a generated setter method.
+For now, the default injection strategy is field injection, but it can be configured with <<configuration-options>>.
+It is recommended to use constructor injection to simplify testing.
+
+When you define mappers in Spring with circular dependencies compilation may fail.
+In that case utilize the `InjectionStrategy#SETTER` strategy.
+
+[TIP]
+====
+For abstract classes or decorators setter injection should be used.
+====

documentation/src/main/asciidoc/chapter-5-data-type-conversions.asciidoc

@@ -0,0 +1,823 @@
+[[datatype-conversions]]
+== Data type conversions
+
+Not always a mapped attribute has the same type in the source and target objects. For instance an attribute may be of type `int` in the source bean but of type `Long` in the target bean.
+
+Another example are references to other objects which should be mapped to the corresponding types in the target model. E.g. the class `Car` might have a property `driver` of the type `Person` which needs to be converted into a `PersonDto` object when mapping a `Car` object.
+
+In this section you'll learn how MapStruct deals with such data type conversions.
+
+[[implicit-type-conversions]]
+=== Implicit type conversions
+
+MapStruct takes care of type conversions automatically in many cases. If for instance an attribute is of type `int` in the source bean but of type `String` in the target bean, the generated code will transparently perform a conversion by calling `String#valueOf(int)` and `Integer#parseInt(String)`, respectively.
+
+Currently the following conversions are applied automatically:
+
+* Between all Java primitive data types and their corresponding wrapper types, e.g. between `int` and `Integer`, `boolean` and `Boolean` etc. The generated code is `null` aware, i.e. when converting a wrapper type into the corresponding primitive type a `null` check will be performed.
+
+* Between all Java primitive number types and the wrapper types, e.g. between `int` and `long` or `byte` and `Integer`.
+
+[WARNING]
+====
+Converting from larger data types to smaller ones (e.g. from `long` to `int`) can cause a value or precision loss. The `Mapper` and `MapperConfig` annotations have a method `typeConversionPolicy` to control warnings / errors. Due to backward compatibility reasons the default value is `ReportingPolicy.IGNORE`.
+====
+
+* Between all Java primitive types (including their wrappers) and `String`, e.g. between `int` and `String` or `Boolean` and `String`. A format string as understood by `java.text.DecimalFormat` can be specified.
+
+.Conversion from int to String
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    @Mapping(source = "price", numberFormat = "$#.00")
+    CarDto carToCarDto(Car car);
+
+    @IterableMapping(numberFormat = "$#.00")
+    List<String> prices(List<Integer> prices);
+}
+----
+====
+* Between `enum` types and `String`.
+
+* Between `enum` types and `Integer`, according to `enum.ordinal()`.
+** When converting from an `Integer`, the value needs to be less than the number of values of the enum, otherwise an `ArrayOutOfBoundsException` is thrown.
+
+* Between big number types (`java.math.BigInteger`, `java.math.BigDecimal`) and Java primitive types (including their wrappers) as well as String. A format string as understood by `java.text.DecimalFormat` can be specified.
+
+.Conversion from BigDecimal to String
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    @Mapping(source = "power", numberFormat = "#.##E0")
+    CarDto carToCarDto(Car car);
+
+}
+----
+====
+
+
+* Between `JAXBElement<T>` and `T`, `List<JAXBElement<T>>` and `List<T>`
+
+* Between `java.util.Calendar`/`java.util.Date` and JAXB's `XMLGregorianCalendar`
+
+* Between `java.util.Date`/`XMLGregorianCalendar` and `String`. A format string as understood by `java.text.SimpleDateFormat` can be specified via the `dateFormat` option as this:
+
+.Conversion from Date to String
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    @Mapping(source = "manufacturingDate", dateFormat = "dd.MM.yyyy")
+    CarDto carToCarDto(Car car);
+
+    @IterableMapping(dateFormat = "dd.MM.yyyy")
+    List<String> stringListToDateList(List<Date> dates);
+}
+----
+====
+
+* Between Jodas `org.joda.time.DateTime`, `org.joda.time.LocalDateTime`, `org.joda.time.LocalDate`, `org.joda.time.LocalTime` and `String`. A format string as understood by `java.text.SimpleDateFormat` can be specified via the `dateFormat` option (see above).
+
+* Between Jodas `org.joda.time.DateTime` and  `javax.xml.datatype.XMLGregorianCalendar`, `java.util.Calendar`.
+
+* Between Jodas `org.joda.time.LocalDateTime`, `org.joda.time.LocalDate` and `javax.xml.datatype.XMLGregorianCalendar`, `java.util.Date`.
+
+* Between `java.time.LocalDate`, `java.time.LocalDateTime` and `javax.xml.datatype.XMLGregorianCalendar`.
+
+* Between `java.time.ZonedDateTime`, `java.time.LocalDateTime`, `java.time.LocalDate`, `java.time.LocalTime` from Java 8 Date-Time package and `String`. A format string as understood by `java.text.SimpleDateFormat` can be specified via the `dateFormat` option (see above).
+
+* Between `java.time.Instant`, `java.time.Duration`, `java.time.Period` from Java 8 Date-Time package and `String` using the `parse` method in each class to map from `String` and using `toString` to map into `String`.
+
+* Between `java.time.ZonedDateTime` from Java 8 Date-Time package and `java.util.Date` where, when mapping a `ZonedDateTime` from a given `Date`, the system default timezone is used.
+
+* Between `java.time.LocalDateTime` from Java 8 Date-Time package and `java.util.Date` where timezone UTC is used as the timezone.
+
+* Between `java.time.LocalDate` from Java 8 Date-Time package and `java.util.Date` / `java.sql.Date` where timezone UTC is used as the timezone.
+
+* Between `java.time.Instant` from Java 8 Date-Time package and `java.util.Date`.
+
+* Between `java.time.LocalDateTime` from Java 8 Date-Time package and `java.time.LocalDate` from the same package.
+
+* Between `java.time.ZonedDateTime` from Java 8 Date-Time package and `java.util.Calendar`.
+
+* Between `java.sql.Date` and `java.util.Date`
+
+* Between `java.sql.Time` and `java.util.Date`
+
+* Between `java.sql.Timestamp` and `java.util.Date`
+
+* When converting from a `String`, omitting `Mapping#dateFormat`, it leads to usage of the default pattern and date format symbols for the default locale. An exception to this rule is `XmlGregorianCalendar` which results in parsing the `String` according to http://www.w3.org/TR/xmlschema-2/#dateTime[XML Schema 1.0 Part 2, Section 3.2.7-14.1, Lexical Representation].
+
+* Between `java.util.Currency` and `String`.
+** When converting from a `String`, the value needs to be a valid https://en.wikipedia.org/wiki/ISO_4217[ISO-4217] alphabetic code otherwise an `IllegalArgumentException` is thrown.
+
+* Between `java.util.UUID` and `String`.
+** When converting from a `String`, the value needs to be a valid https://en.wikipedia.org/wiki/Universally_unique_identifier[UUID] otherwise an `IllegalArgumentException` is thrown.
+
+* Between `String` and `StringBuilder`
+
+* Between `java.net.URL` and `String`.
+** When converting from a `String`, the value needs to be a valid https://en.wikipedia.org/wiki/URL[URL] otherwise a `MalformedURLException` is thrown.
+
+* Between `java.util.Locale` and `String`.
+** When converting from a `Locale`, the resulting `String` will be a well-formed IETF BCP 47 language tag representing the locale. When converting from a `String`, the locale that best represents the language tag will be returned. See https://docs.oracle.com/javase/8/docs/api/java/util/Locale.html#forLanguageTag-java.lang.String-[Locale.forLanguageTag()] and https://docs.oracle.com/javase/8/docs/api/java/util/Locale.html#toLanguageTag--[Locale.toLanguageTag()] for more information.
+
+[[mapping-object-references]]
+=== Mapping object references
+
+Typically an object has not only primitive attributes but also references other objects. E.g. the `Car` class could contain a reference to a `Person` object (representing the car's driver) which should be mapped to a `PersonDto` object referenced by the `CarDto` class.
+
+In this case just define a mapping method for the referenced object type as well:
+
+.Mapper with one mapping method using another
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    CarDto carToCarDto(Car car);
+
+    PersonDto personToPersonDto(Person person);
+}
+----
+====
+
+The generated code for the `carToCarDto()` method will invoke the `personToPersonDto()` method for mapping the `driver` attribute, while the generated implementation for `personToPersonDto()` performs the mapping of person objects.
+
+That way it is possible to map arbitrary deep object graphs. When mapping from entities into data transfer objects it is often useful to cut references to other entities at a certain point. To do so, implement a custom mapping method (see the next section) which e.g. maps a referenced entity to its id in the target object.
+
+When generating the implementation of a mapping method, MapStruct will apply the following routine for each attribute pair in the source and target object:
+
+. If source and target attribute have the same type, the value will be simply copied *direct* from source to target. If the attribute is a collection (e.g. a `List`) a copy of the collection will be set into the target attribute.
+. If source and target attribute type differ, check whether there is another *mapping method* which has the type of the source attribute as parameter type and the type of the target attribute as return type. If such a method exists it will be invoked in the generated mapping implementation.
+. If no such method exists MapStruct will look whether a *built-in conversion* for the source and target type of the attribute exists. If this is the case, the generated mapping code will apply this conversion.
+. If no such method exists MapStruct will apply *complex* conversions:
+.. mapping method, the result mapped by mapping method, like this: `target = method1( method2( source ) )`
+.. built-in conversion, the result mapped by mapping method, like this: `target = method( conversion( source ) )`
+.. mapping method, the result mapped by build-in conversion, like this: `target = conversion( method( source ) )`
+. If no such method was found MapStruct will try to generate an automatic sub-mapping method that will do the mapping between the source and target attributes.
+. If MapStruct could not create a name based mapping method an error will be raised at build time, indicating the non-mappable attribute and its path.
+
+A mapping control (`MappingControl`) can be defined on all levels (`@MapperConfig`, `@Mapper`, `@BeanMapping`, `@Mapping`), the latter taking precedence over the former. For example: `@Mapper( mappingControl = NoComplexMapping.class )` takes precedence over `@MapperConfig( mappingControl = DeepClone.class )`. `@IterableMapping` and `@MapMapping` work similar as `@Mapping`. MappingControl is experimental from MapStruct 1.4.
+`MappingControl` has an enum that corresponds to the first 4 options above: `MappingControl.Use#DIRECT`, `MappingControl.Use#MAPPING_METHOD`, `MappingControl.Use#BUILT_IN_CONVERSION` and `MappingControl.Use#COMPLEX_MAPPING` the presence of which allows the user to switch *on* a option. The absence of an enum switches *off* a mapping option. Default they are all present enabling all mapping options.
+
+[NOTE]
+====
+In order to stop MapStruct from generating automatic sub-mapping methods as in 5. above, one can use `@Mapper( disableSubMappingMethodsGeneration = true )`.
+====
+
+[TIP]
+====
+The user has full control over the mapping by means of meta annotations. Some handy ones have been defined such as `@DeepClone` which only allows direct mappings. The result: if source and target type are the same, MapStruct will make a deep clone of the source. Sub-mappings-methods have to be allowed (default option).
+====
+
+[NOTE]
+====
+During the generation of automatic sub-mapping methods <<shared-configurations>> will not be taken into consideration, yet.
+Follow issue https://github.com/mapstruct/mapstruct/issues/1086[#1086] for more information.
+====
+
+[NOTE]
+====
+Constructor properties of the target object are also considered as target properties.
+You can read more about that in <<mapping-with-constructors>>
+====
+
+[[controlling-nested-bean-mappings]]
+=== Controlling nested bean mappings
+
+As explained above, MapStruct will generate a method based on the name of the source and target property. Unfortunately, in many occasions these names do not match.
+
+The ‘.’ notation in an `@Mapping` source or target type can be used to control how properties should be mapped when names do not match.
+There is an elaborate https://github.com/mapstruct/mapstruct-examples/tree/master/mapstruct-nested-bean-mappings[example] in our examples repository to explain how this problem can be overcome.
+
+In the simplest scenario there’s a property on a nested level that needs to be corrected.
+Take for instance a property `fish` which has an identical name in `FishTankDto` and `FishTank`.
+For this property MapStruct automatically generates a mapping: `FishDto fishToFishDto(Fish fish)`.
+MapStruct cannot possibly be aware of the deviating properties `kind` and `type`.
+Therefore this can be addressed in a mapping rule: `@Mapping(target="fish.kind", source="fish.type")`.
+This tells MapStruct to deviate from looking for a name `kind` at this level and map it to `type`.
+
+.Mapper controlling nested beans mappings I
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface FishTankMapper {
+
+    @Mapping(target = "fish.kind", source = "fish.type")
+    @Mapping(target = "fish.name", ignore = true)
+    @Mapping(target = "ornament", source = "interior.ornament")
+    @Mapping(target = "material.materialType", source = "material")
+    @Mapping(target = "quality.report.organisation.name", source = "quality.report.organisationName")
+    FishTankDto map( FishTank source );
+}
+----
+====
+
+The same constructs can be used to ignore certain properties at a nesting level, as is demonstrated in the second `@Mapping` rule.
+
+MapStruct can even be used to “cherry pick” properties when source and target do not share the same nesting level (the same number of properties).
+This can be done in the source – and in the target type. This is demonstrated in the next 2 rules: `@Mapping(target="ornament", source="interior.ornament")` and `@Mapping(target="material.materialType", source="material")`.
+
+The latter can even be done when mappings first share a common base.
+For example: all properties that share the same name of `Quality` are mapped to `QualityDto`.
+Likewise, all properties of `Report` are mapped to `ReportDto`, with one exception: `organisation` in `OrganisationDto` is left empty (since there is no organization at the source level).
+Only the `name` is populated with the `organisationName` from `Report`.
+This is demonstrated in `@Mapping(target="quality.report.organisation.name", source="quality.report.organisationName")`
+
+Coming back to the original example: what if `kind` and `type` would be beans themselves?
+In that case MapStruct would again generate a method continuing to map.
+Such is demonstrated in the next example:
+
+
+.Mapper controlling nested beans mappings II
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface FishTankMapperWithDocument {
+
+    @Mapping(target = "fish.kind", source = "fish.type")
+    @Mapping(target = "fish.name", expression = "java(\"Jaws\")")
+    @Mapping(target = "plant", ignore = true )
+    @Mapping(target = "ornament", ignore = true )
+    @Mapping(target = "material", ignore = true)
+    @Mapping(target = "quality.document", source = "quality.report")
+    @Mapping(target = "quality.document.organisation.name", constant = "NoIdeaInc" )
+    FishTankWithNestedDocumentDto map( FishTank source );
+
+}
+----
+====
+
+Note what happens in `@Mapping(target="quality.document", source="quality.report")`.
+`DocumentDto` does not exist as such on the target side. It is mapped from `Report`.
+MapStruct continues to generate mapping code here. That mapping itself can be guided towards another name.
+This even works for constants and expression. Which is shown in the final example: `@Mapping(target="quality.document.organisation.name", constant="NoIdeaInc")`.
+
+MapStruct will perform a null check on each nested property in the source.
+
+[TIP]
+====
+Instead of configuring everything via the parent method we encourage users to explicitly write their own nested methods.
+This puts the configuration of the nested mapping into one place (method) where it can be reused from several methods in the upper level,
+instead of re-configuring the same things on all of those upper methods.
+====
+
+[TIP]
+====
+When ignoring multiple properties instead of defining multiple `@Mapping` annotations, you can use the `@Ignored` annotation to group them together.
+e.g. for the `FishTankMapperWithDocument` example above, you could write:
+`@Ignored(targets = { "plant", "ornament", "material" })`
+====
+
+[NOTE]
+====
+In some cases the `ReportingPolicy` that is going to be used for the generated nested method would be `IGNORE`.
+This means that it is possible for MapStruct not to report unmapped target properties in nested mappings.
+====
+
+
+[[invoking-custom-mapping-method]]
+=== Invoking custom mapping method
+
+Sometimes mappings are not straightforward and some fields require custom logic.
+
+The example below demonstrates how the properties `length`, `width` and `height` in `FishTank` can be mapped to the `VolumeDto` bean, which is a member of `FishTankWithVolumeDto`. `VolumeDto` contains the properties `volume` and `description`. Custom logic is achieved by defining a method which takes `FishTank` instance as a parameter and returns a `VolumeDto`. MapStruct will take the entire parameter `source` and generate code to call the custom method `mapVolume` in order to map the `FishTank` object to the target property `volume`.
+
+The remainder of the fields could be mapped the regular way: using mappings defined defined by means of `@Mapping` annotations.
+
+.Manually implemented mapping method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class FishTank {
+    Fish fish;
+    String material;
+    Quality quality;
+    int length;
+    int width;
+    int height;
+}
+
+public class FishTankWithVolumeDto {
+    FishDto fish;
+    MaterialDto material;
+    QualityDto quality;
+    VolumeDto volume;
+}
+
+public class VolumeDto {
+    int volume;
+    String description;
+}
+
+@Mapper
+public abstract class FishTankMapperWithVolume {
+
+    @Mapping(target = "fish.kind", source = "source.fish.type")
+    @Mapping(target = "material.materialType", source = "source.material")
+    @Mapping(target = "quality.document", source = "source.quality.report")
+    @Mapping(target = "volume", source = "source")
+    abstract FishTankWithVolumeDto map(FishTank source);
+
+    VolumeDto mapVolume(FishTank source) {
+        int volume = source.length * source.width * source.height;
+        String desc = volume < 100 ? "Small" : "Large";
+        return new VolumeDto(volume, desc);
+    }
+}
+----
+====
+
+Note the `@Mapping` annotation where `source` field is equal to `"source"`, indicating the parameter name `source` itself in the method `map(FishTank source)` instead of a (target) property in `FishTank`.
+
+
+[[invoking-other-mappers]]
+=== Invoking other mappers
+
+In addition to methods defined on the same mapper type MapStruct can also invoke mapping methods defined in other classes, be it mappers generated by MapStruct or hand-written mapping methods. This can be useful to structure your mapping code in several classes (e.g. with one mapper type per application module) or if you want to provide custom mapping logic which can't be generated by MapStruct.
+
+For instance the `Car` class might contain an attribute `manufacturingDate` while the corresponding DTO attribute is of type String. In order to map this attribute, you could implement a mapper class like this:
+
+.Manually implemented mapper class
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class DateMapper {
+
+    public String asString(Date date) {
+        return date != null ? new SimpleDateFormat( "yyyy-MM-dd" )
+            .format( date ) : null;
+    }
+
+    public Date asDate(String date) {
+        try {
+            return date != null ? new SimpleDateFormat( "yyyy-MM-dd" )
+                .parse( date ) : null;
+        }
+        catch ( ParseException e ) {
+            throw new RuntimeException( e );
+        }
+    }
+}
+----
+====
+
+In the `@Mapper` annotation at the `CarMapper` interface reference the `DateMapper` class like this:
+
+.Referencing another mapper class
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper(uses=DateMapper.class)
+public interface CarMapper {
+
+    CarDto carToCarDto(Car car);
+}
+----
+====
+
+When generating code for the implementation of the `carToCarDto()` method, MapStruct will look for a method which maps a `Date` object into a String, find it on the `DateMapper` class and generate an invocation of `asString()` for mapping the `manufacturingDate` attribute.
+
+Generated mappers retrieve referenced mappers using the component model configured for them. If e.g. CDI was used as component model for `CarMapper`, `DateMapper` would have to be a CDI bean as well. When using the default component model, any hand-written mapper classes to be referenced by MapStruct generated mappers must declare a public no-args constructor in order to be instantiable.
+
+[[passing-target-type]]
+=== Passing the mapping target type to custom mappers
+
+When having a custom mapper hooked into the generated mapper with `@Mapper#uses()`, an additional parameter of type `Class` (or a super-type of it) can be defined in the custom mapping method in order to perform general mapping tasks for specific target object types. That attribute must be annotated with `@TargetType` for MapStruct to generate calls that pass the `Class` instance representing the corresponding property type of the target bean.
+
+For instance, the `CarDto` could have a property `owner` of type `Reference` that contains the primary key of a `Person` entity. You could now create a generic custom mapper that resolves any `Reference` objects to their corresponding managed JPA entity instances.
+
+e.g.
+
+.Example classes for the passing target type example
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class Car {
+
+    private Person owner;
+    // ...
+}
+
+public class Person extends BaseEntity {
+
+    // ...
+}
+
+public class Reference {
+
+    private String pk;
+    // ...
+}
+
+public class CarDto {
+
+    private Reference owner;
+    // ...
+}
+----
+====
+
+
+.Mapping method expecting mapping target type as parameter
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@ApplicationScoped // CDI component model
+public class ReferenceMapper {
+
+    @PersistenceContext
+    private EntityManager entityManager;
+
+    public <T extends BaseEntity> T resolve(Reference reference, @TargetType Class<T> entityClass) {
+        return reference != null ? entityManager.find( entityClass, reference.getPk() ) : null;
+    }
+
+    public Reference toReference(BaseEntity entity) {
+        return entity != null ? new Reference( entity.getPk() ) : null;
+    }
+}
+
+@Mapper(componentModel = MappingConstants.ComponentModel.CDI, uses = ReferenceMapper.class )
+public interface CarMapper {
+
+    Car carDtoToCar(CarDto carDto);
+}
+----
+====
+
+MapStruct will then generate something like this:
+
+.Generated code
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+//GENERATED CODE
+@ApplicationScoped
+public class CarMapperImpl implements CarMapper {
+
+    @Inject
+    private ReferenceMapper referenceMapper;
+
+    @Override
+    public Car carDtoToCar(CarDto carDto) {
+        if ( carDto == null ) {
+            return null;
+        }
+
+        Car car = new Car();
+
+        car.setOwner( referenceMapper.resolve( carDto.getOwner(), Owner.class ) );
+        // ...
+
+        return car;
+    }
+}
+----
+====
+
+[[passing-context]]
+=== Passing context or state objects to custom methods
+
+Additional _context_ or _state_ information can be passed through generated mapping methods to custom methods with `@Context` parameters. Such parameters are passed to other mapping methods, `@ObjectFactory` methods (see <<object-factories>>) or `@BeforeMapping` / `@AfterMapping` methods (see <<customizing-mappings-with-before-and-after>>) when applicable and can thus be used in custom code.
+
+`@Context` parameters are searched for `@ObjectFactory` methods, which are called on the provided context parameter value if applicable.
+
+`@Context` parameters are also searched for `@BeforeMapping` / `@AfterMapping` methods, which are called on the provided context parameter value if applicable.
+
+*Note:* no `null` checks are performed before calling before/after mapping methods on context parameters. The caller needs to make sure that `null` is not passed in that case.
+
+For generated code to call a method that is declared with `@Context` parameters, the declaration of the mapping method being generated needs to contain at least those (or assignable) `@Context` parameters as well. The generated code will not create new instances of missing `@Context` parameters nor will it pass a literal `null` instead.
+
+.Using `@Context` parameters for passing data down to hand-written property mapping methods
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public abstract CarDto toCar(Car car, @Context Locale translationLocale);
+
+protected OwnerManualDto translateOwnerManual(OwnerManual ownerManual, @Context Locale locale) {
+    // manually implemented logic to translate the OwnerManual with the given Locale
+}
+----
+====
+
+MapStruct will then generate something like this:
+
+.Generated code
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+//GENERATED CODE
+public CarDto toCar(Car car, Locale translationLocale) {
+    if ( car == null ) {
+        return null;
+    }
+
+    CarDto carDto = new CarDto();
+
+    carDto.setOwnerManual( translateOwnerManual( car.getOwnerManual(), translationLocale );
+    // more generated mapping code
+
+    return carDto;
+}
+----
+====
+
+
+[[mapping-method-resolution]]
+=== Mapping method resolution
+
+When mapping a property from one type to another, MapStruct looks for the most specific method which maps the source type into the target type. The method may either be declared on the same mapper interface or on another mapper which is registered via `@Mapper#uses()`. The same applies for factory methods (see <<object-factories>>).
+
+The algorithm for finding a mapping or factory method resembles Java's method resolution algorithm as much as possible. In particular, methods with a more specific source type will take precedence (e.g. if there are two methods, one which maps the searched source type, and another one which maps a super-type of the same). In case more than one most-specific method is found, an error will be raised.
+
+[TIP]
+====
+When working with JAXB, e.g. when converting a `String` to a corresponding `JAXBElement<String>`, MapStruct will take the `scope` and `name` attributes of `@XmlElementDecl` annotations into account when looking for a mapping method. This makes sure that the created `JAXBElement` instances will have the right QNAME value. You can find a test which maps JAXB objects https://github.com/mapstruct/mapstruct/blob/{mapstructVersion}/integrationtest/src/test/resources/jaxbTest/src/test/java/org/mapstruct/itest/jaxb/JaxbBasedMapperTest.java[here].
+====
+
+[[selection-based-on-qualifiers]]
+=== Mapping method selection based on qualifiers
+
+In many occasions one requires mapping methods with the same method signature (apart from the name) that have different behavior.
+MapStruct has a handy mechanism to deal with such situations: `@Qualifier` (`org.mapstruct.Qualifier`).
+A ‘qualifier’ is a custom annotation that the user can write, ‘stick onto’ a mapping method which is included as used mapper
+and can be referred to in a bean property mapping, iterable mapping or map mapping.
+Multiple qualifiers can be ‘stuck onto’ a method and mapping.
+
+So, let's say there is a hand-written method to map titles with a `String` return type and `String` argument amongst many other referenced mappers with the same `String` return type  - `String` argument signature:
+
+.Several mapping methods with identical source and target types
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class Titles {
+
+    public String translateTitleEG(String title) {
+        // some mapping logic
+    }
+
+    public String translateTitleGE(String title) {
+        // some mapping logic
+    }
+}
+----
+====
+
+And a mapper using this handwritten mapper, in which source and target have a property 'title' that should be mapped:
+
+.Mapper causing an ambiguous mapping method error
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper( uses = Titles.class )
+public interface MovieMapper {
+
+     GermanRelease toGerman( OriginalRelease movies );
+
+}
+----
+====
+
+Without the use of qualifiers, this would result in an ambiguous mapping method error, because 2 qualifying methods are found (`translateTitleEG`, `translateTitleGE`) and MapStruct would not have a hint which one to choose.
+
+Enter the qualifier approach:
+
+.Declaring a qualifier type
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+import org.mapstruct.Qualifier;
+
+@Qualifier
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.CLASS)
+public @interface TitleTranslator {
+}
+----
+====
+
+And, some qualifiers to indicate which translator to use to map from source language to target language:
+
+.Declaring qualifier types for mapping methods
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+import org.mapstruct.Qualifier;
+
+@Qualifier
+@Target(ElementType.METHOD)
+@Retention(RetentionPolicy.CLASS)
+public @interface EnglishToGerman {
+}
+----
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+import org.mapstruct.Qualifier;
+
+@Qualifier
+@Target(ElementType.METHOD)
+@Retention(RetentionPolicy.CLASS)
+public @interface GermanToEnglish {
+}
+----
+====
+
+Please take note of the target `TitleTranslator` on type level, `EnglishToGerman`, `GermanToEnglish` on method level!
+
+Then, using the qualifiers, the mapping could look like this:
+
+.Mapper using qualifiers
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper( uses = Titles.class )
+public interface MovieMapper {
+
+     @Mapping( target = "title", qualifiedBy = { TitleTranslator.class, EnglishToGerman.class } )
+     GermanRelease toGerman( OriginalRelease movies );
+
+}
+----
+====
+
+.Custom mapper qualifying the methods it provides
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@TitleTranslator
+public class Titles {
+
+    @EnglishToGerman
+    public String translateTitleEG(String title) {
+        // some mapping logic
+    }
+
+    @GermanToEnglish
+    public String translateTitleGE(String title) {
+        // some mapping logic
+    }
+}
+----
+====
+
+[WARNING]
+====
+Please make sure the used retention policy equals retention policy `CLASS` (`@Retention(RetentionPolicy.CLASS)`).
+====
+
+[WARNING]
+====
+A class / method annotated with a qualifier will not qualify anymore for mappings that do not have the `qualifiedBy` element.
+====
+
+[TIP]
+====
+The same mechanism is also present on bean mappings: `@BeanMapping#qualifiedBy`: it selects the factory method marked with the indicated qualifier.
+====
+
+In many occasions, declaring a new annotation to aid the selection process can be too much for what you try to achieve. For those situations, MapStruct has the `@Named` annotation. This annotation is a pre-defined qualifier (annotated with `@Qualifier` itself) and can be used to name a Mapper or, more directly a mapping method by means of its value. The same example above would look like:
+
+.Custom mapper, annotating the methods to qualify by means of `@Named`
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Named("TitleTranslator")
+public class Titles {
+
+    @Named("EnglishToGerman")
+    public String translateTitleEG(String title) {
+        // some mapping logic
+    }
+
+    @Named("GermanToEnglish")
+    public String translateTitleGE(String title) {
+        // some mapping logic
+    }
+}
+----
+====
+
+.Mapper using named
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper( uses = Titles.class )
+public interface MovieMapper {
+
+     @Mapping( target = "title", qualifiedByName = { "TitleTranslator", "EnglishToGerman" } )
+     GermanRelease toGerman( OriginalRelease movies );
+
+}
+----
+====
+
+[WARNING]
+====
+Although the used mechanism is the same, the user has to be a bit more careful. Refactoring the name of a defined qualifier in an IDE will neatly refactor all other occurrences as well. This is obviously not the case for changing a name.
+====
+
+=== Combining qualifiers with defaults
+Please note that the `Mapping#defaultValue` is in essence a `String`, which needs to be converted to the `Mapping#target`. Providing a `Mapping#qualifiedByName` or `Mapping#qualifiedBy` will force MapStruct to use that method. If you want different behavior for the `Mapping#defaultValue`, then please provide an appropriate mapping method. This mapping method needs to transforms a `String` into the desired type of `Mapping#target` and also be annotated so that it can be found by the `Mapping#qualifiedByName` or `Mapping#qualifiedBy`.
+
+.Mapper using defaultValue
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface MovieMapper {
+
+     @Mapping( target = "category", qualifiedByName = "CategoryToString", defaultValue = "DEFAULT" )
+     GermanRelease toGerman( OriginalRelease movies );
+
+     @Named("CategoryToString")
+     default String defaultValueForQualifier(Category cat) {
+         // some mapping logic
+     }
+}
+----
+====
+
+In the above example in case that category is null, the method `CategoryToString( Enum.valueOf( Category.class, "DEFAULT" ) )` will be called and the result will be set to the category field.
+
+.Mapper using defaultValue and default method.
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface MovieMapper {
+
+     @Mapping( target = "category", qualifiedByName = "CategoryToString", defaultValue = "Unknown" )
+     GermanRelease toGerman( OriginalRelease movies );
+
+     @Named("CategoryToString")
+     default String defaultValueForQualifier(Category cat) {
+         // some mapping logic
+     }
+
+     @Named("CategoryToString")
+     default String defaultValueForQualifier(String value) {
+         return value;
+     }
+}
+----
+====
+In the above example in case that category is null, the method `defaultValueForQualifier( "Unknown" )` will be called and the result will be set to the category field.
+
+If the above mentioned methods do not work there is the option to use `defaultExpression` to set the default value.
+
+.Mapper using defaultExpression
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface MovieMapper {
+
+     @Mapping( target = "category", qualifiedByName = "CategoryToString", defaultExpression = "java(\"Unknown\")" )
+     GermanRelease toGerman( OriginalRelease movies );
+
+     @Named("CategoryToString")
+     default String defaultValueForQualifier(Category cat) {
+         // some mapping logic
+     }
+}
+----
+====

documentation/src/main/asciidoc/chapter-6-mapping-collections.asciidoc

@@ -0,0 +1,231 @@
+[[mapping-collections]]
+== Mapping collections
+
+The mapping of collection types (`List`, `Set` etc.) is done in the same way as mapping bean types, i.e. by defining mapping methods with the required source and target types in a mapper interface. MapStruct supports a wide range of iterable types from the http://docs.oracle.com/javase/tutorial/collections/intro/index.html[Java Collection Framework].
+
+The generated code will contain a loop which iterates over the source collection, converts each element and puts it into the target collection. If a mapping method for the collection element types is found in the given mapper or the mapper it uses, this method is invoked to perform the element conversion. Alternatively, if an implicit conversion for the source and target element types exists, this conversion routine will be invoked. The following shows an example:
+
+.Mapper with collection mapping methods
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CarMapper {
+
+    Set<String> integerSetToStringSet(Set<Integer> integers);
+
+    List<CarDto> carsToCarDtos(List<Car> cars);
+
+    CarDto carToCarDto(Car car);
+}
+----
+====
+
+The generated implementation of the `integerSetToStringSet` performs the conversion from `Integer` to `String` for each element, while the generated `carsToCarDtos()` method invokes the `carToCarDto()` method for each contained element as shown in the following:
+
+.Generated collection mapping methods
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+//GENERATED CODE
+@Override
+public Set<String> integerSetToStringSet(Set<Integer> integers) {
+    if ( integers == null ) {
+        return null;
+    }
+
+    Set<String> set = new LinkedHashSet<String>();
+
+    for ( Integer integer : integers ) {
+        set.add( String.valueOf( integer ) );
+    }
+
+    return set;
+}
+
+@Override
+public List<CarDto> carsToCarDtos(List<Car> cars) {
+    if ( cars == null ) {
+        return null;
+    }
+
+    List<CarDto> list = new ArrayList<CarDto>();
+
+    for ( Car car : cars ) {
+        list.add( carToCarDto( car ) );
+    }
+
+    return list;
+}
+----
+====
+
+Note that MapStruct will look for a collection mapping method with matching parameter and return type, when mapping a collection-typed attribute of a bean, e.g. from `Car#passengers` (of type `List<Person>`) to `CarDto#passengers` (of type `List<PersonDto>`).
+
+.Usage of collection mapping method to map a bean property
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+//GENERATED CODE
+carDto.setPassengers( personsToPersonDtos( car.getPassengers() ) );
+...
+----
+====
+
+Some frameworks and libraries only expose JavaBeans getters but no setters for collection-typed properties. Types generated from an XML schema using JAXB adhere to this pattern by default. In this case the generated code for mapping such a property invokes its getter and adds all the mapped elements:
+
+.Usage of an adding method for collection mapping
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+//GENERATED CODE
+carDto.getPassengers().addAll( personsToPersonDtos( car.getPassengers() ) );
+...
+----
+====
+
+[WARNING]
+====
+It is not allowed to declare mapping methods with an iterable source (from a java package) and a non-iterable target or the other way around. An error will be raised when detecting this situation.
+====
+
+[[mapping-maps]]
+=== Mapping maps
+
+Also map-based mapping methods are supported. The following shows an example:
+
+.Map mapping method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public interface SourceTargetMapper {
+
+    @MapMapping(valueDateFormat = "dd.MM.yyyy")
+    Map<String, String> longDateMapToStringStringMap(Map<Long, Date> source);
+}
+----
+====
+
+Similar to iterable mappings, the generated code will iterate through the source map, convert each value and key (either by means of an implicit conversion or by invoking another mapping method) and put them into the target map:
+
+.Generated implementation of map mapping method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+//GENERATED CODE
+@Override
+public Map<Long, Date> stringStringMapToLongDateMap(Map<String, String> source) {
+    if ( source == null ) {
+        return null;
+    }
+
+    Map<Long, Date> map = new LinkedHashMap<Long, Date>();
+
+    for ( Map.Entry<String, String> entry : source.entrySet() ) {
+
+        Long key = Long.parseLong( entry.getKey() );
+        Date value;
+        try {
+            value = new SimpleDateFormat( "dd.MM.yyyy" ).parse( entry.getValue() );
+        }
+        catch( ParseException e ) {
+            throw new RuntimeException( e );
+        }
+
+        map.put( key, value );
+    }
+
+    return map;
+}
+----
+====
+
+[[collection-mapping-strategies]]
+=== Collection mapping strategies
+
+MapStruct has a `CollectionMappingStrategy`, with the possible values: `ACCESSOR_ONLY`, `SETTER_PREFERRED`, `ADDER_PREFERRED` and `TARGET_IMMUTABLE`.
+
+In the table below, the dash `-` indicates a property name. Next, the trailing `s` indicates the plural form. The table explains the options and how they are applied to the presence/absence of a `set-s`, `add-` and / or `get-s` method on the target object:
+
+.Collection mapping strategy options
+|===
+|Option|Only target set-s Available|Only target add- Available|Both set-s / add- Available|No set-s / add- Available|Existing Target(`@TargetType`)
+
+|`ACCESSOR_ONLY`
+|set-s
+|get-s
+|set-s
+|get-s
+|get-s
+
+|`SETTER_PREFERRED`
+|set-s
+|add-
+|set-s
+|get-s
+|get-s
+
+|`ADDER_PREFERRED`
+|set-s
+|add-
+|add-
+|get-s
+|get-s
+
+|`TARGET_IMMUTABLE`
+|set-s
+|exception
+|set-s
+|exception
+|set-s
+|===
+
+Some background: An `adder` method is typically used in case of http://www.eclipse.org/webtools/dali/[generated (JPA) entities], to add a single element (entity) to an underlying collection. Invoking the adder establishes a parent-child relation between parent - the bean (entity) on which the adder is invoked - and its child(ren), the elements (entities) in the collection. To find the appropriate `adder`, MapStruct will try to make a match between the generic parameter type of the underlying collection and the single argument of a candidate `adder`. When there are more candidates, the plural `setter` / `getter` name is converted to singular and will be used in addition to make a match.
+
+The option `DEFAULT` should not be used explicitly. It is used to distinguish between an explicit user desire to override the default in a `@MapperConfig` from the implicit Mapstruct choice in a `@Mapper`. The option `DEFAULT` is synonymous to `ACCESSOR_ONLY`.
+
+[TIP]
+====
+When working with an `adder` method and JPA entities, Mapstruct assumes that the target collections are initialized with a collection implementation (e.g. an `ArrayList`). You can use factories to create a new target entity with initialized collections instead of Mapstruct creating the target entity by its constructor.
+====
+
+[[implementation-types-for-collection-mappings]]
+=== Implementation types used for collection mappings
+
+When an iterable or map mapping method declares an interface type as return type, one of its implementation types will be instantiated in the generated code. The following table shows the supported interface types and their corresponding implementation types as instantiated in the generated code:
+
+.Collection mapping implementation types
+|===
+|Interface type|Implementation type
+
+|`Iterable`|`ArrayList`
+
+|`Collection`|`ArrayList`
+
+|`List`|`ArrayList`
+
+|`Set`|`LinkedHashSet`
+
+|`SequencedSet`|`LinkedHashSet`
+
+|`SortedSet`|`TreeSet`
+
+|`NavigableSet`|`TreeSet`
+
+|`Map`|`LinkedHashMap`
+
+|`SequencedMap`|`LinkedHashMap`
+
+|`SortedMap`|`TreeMap`
+
+|`NavigableMap`|`TreeMap`
+
+|`ConcurrentMap`|`ConcurrentHashMap`
+|`ConcurrentNavigableMap`|`ConcurrentSkipListMap`
+|===

documentation/src/main/asciidoc/chapter-7-mapping-streams.asciidoc

@@ -41,8 +41,8 @@ public Set<String> integerStreamToStringSet(Stream<Integer> integers) {
         return null;
     }
 
-    return integers.stream().map( integer -> String.valueOf( integer ) )
-        .collect( Collectors.toCollection( HashSet<String>::new ) );
+    return integers.map( integer -> String.valueOf( integer ) )
+        .collect( Collectors.toCollection( LinkedHashSet<String>::new ) );
 }
 
 @Override
@@ -51,7 +51,7 @@ public List<CarDto> carsToCarDtos(Stream<Car> cars) {
         return null;
     }
 
-    return integers.stream().map( car -> carToCarDto( car ) )
+    return cars.map( car -> carToCarDto( car ) )
         .collect( Collectors.toCollection( ArrayList<CarDto>::new ) );
 }
 ----

documentation/src/main/asciidoc/chapter-8-mapping-values.asciidoc

@@ -0,0 +1,356 @@
+[[mapping-enum-types]]
+== Mapping Values
+
+=== Mapping enum to enum types
+
+MapStruct supports the generation of methods which map one Java enum type into another.
+
+By default, each constant from the source enum is mapped to a constant with the same name in the target enum type. If required, a constant from the source enum may be mapped to a constant with another name with help of the `@ValueMapping` annotation. Several constants from the source enum can be mapped to the same constant in the target type.
+
+The following shows an example:
+
+.Enum mapping method
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface OrderMapper {
+
+    OrderMapper INSTANCE = Mappers.getMapper( OrderMapper.class );
+
+    @ValueMappings({
+        @ValueMapping(target = "SPECIAL", source = "EXTRA"),
+        @ValueMapping(target = "DEFAULT", source = "STANDARD"),
+        @ValueMapping(target = "DEFAULT", source = "NORMAL")
+    })
+    ExternalOrderType orderTypeToExternalOrderType(OrderType orderType);
+}
+----
+====
+
+.Enum mapping method result
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class OrderMapperImpl implements OrderMapper {
+
+    @Override
+    public ExternalOrderType orderTypeToExternalOrderType(OrderType orderType) {
+        if ( orderType == null ) {
+            return null;
+        }
+
+        ExternalOrderType externalOrderType_;
+
+        switch ( orderType ) {
+            case EXTRA: externalOrderType_ = ExternalOrderType.SPECIAL;
+            break;
+            case STANDARD: externalOrderType_ = ExternalOrderType.DEFAULT;
+            break;
+            case NORMAL: externalOrderType_ = ExternalOrderType.DEFAULT;
+            break;
+            case RETAIL: externalOrderType_ = ExternalOrderType.RETAIL;
+            break;
+            case B2B: externalOrderType_ = ExternalOrderType.B2B;
+            break;
+            default: throw new IllegalArgumentException( "Unexpected enum constant: " + orderType );
+        }
+
+        return externalOrderType_;
+    }
+}
+----
+====
+By default an error will be raised by MapStruct in case a constant of the source enum type does not have a corresponding constant with the same name in the target type and also is not mapped to another constant via `@ValueMapping`. This ensures that all constants are mapped in a safe and predictable manner. The generated
+mapping method will throw an `IllegalStateException` if for some reason an unrecognized source value occurs.
+
+MapStruct also has a mechanism for mapping any remaining (unspecified) mappings to a default. This can be used only once in a set of value mappings and only applies to the source. It comes in two flavors: `<ANY_REMAINING>` and `<ANY_UNMAPPED>`. They cannot be used at the same time.
+
+In case of source `<ANY_REMAINING>` MapStruct will continue to map a source enum constant to a target enum constant with the same name. The remainder of the source enum constants will be mapped to the target specified in the `@ValueMapping` with `<ANY_REMAINING>` source.
+
+MapStruct will *not* attempt such name based mapping for `<ANY_UNMAPPED>` and directly apply the target specified in the `@ValueMapping` with `<ANY_UNMAPPED>` source to the remainder.
+
+MapStruct is able to handle `null` sources and `null` targets by means of the `<NULL>` keyword.
+
+In addition, the constant value `<THROW_EXCEPTION>` can be used for throwing an exception for particular value mappings. This value is only applicable to `ValueMapping#target()` and not `ValueMapping#source()` since MapStruct can't map from exceptions.
+
+[TIP]
+====
+Constants for `<ANY_REMAINING>`, `<ANY_UNMAPPED>`, `<THROW_EXCEPTION>` and `<NULL>` are available in the `MappingConstants` class.
+====
+
+Finally `@InheritInverseConfiguration` and `@InheritConfiguration` can be used in combination with `@ValueMappings`. `<ANY_REMAINING>` and `<ANY_UNMAPPED>` will be ignored in that case.
+
+The following code snippets exemplify the use of the aforementioned constants.
+
+.Enum mapping method, `<NULL>` and `<ANY_REMAINING>`
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface SpecialOrderMapper {
+
+    SpecialOrderMapper INSTANCE = Mappers.getMapper( SpecialOrderMapper.class );
+
+    @ValueMappings({
+        @ValueMapping( source = MappingConstants.NULL, target = "DEFAULT" ),
+        @ValueMapping( source = "STANDARD", target = MappingConstants.NULL ),
+        @ValueMapping( source = MappingConstants.ANY_REMAINING, target = "SPECIAL" )
+    })
+    ExternalOrderType orderTypeToExternalOrderType(OrderType orderType);
+}
+----
+====
+
+.Enum mapping method result, `<NULL>` and `<ANY_REMAINING>`
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class SpecialOrderMapperImpl implements SpecialOrderMapper {
+
+    @Override
+    public ExternalOrderType orderTypeToExternalOrderType(OrderType orderType) {
+        if ( orderType == null ) {
+            return ExternalOrderType.DEFAULT;
+        }
+
+        ExternalOrderType externalOrderType_;
+
+        switch ( orderType ) {
+            case STANDARD: externalOrderType_ = null;
+            break;
+            case RETAIL: externalOrderType_ = ExternalOrderType.RETAIL;
+            break;
+            case B2B: externalOrderType_ = ExternalOrderType.B2B;
+            break;
+            default: externalOrderType_ = ExternalOrderType.SPECIAL;
+        }
+
+        return externalOrderType_;
+    }
+}
+----
+====
+
+*Note:* MapStruct would have refrained from mapping the `RETAIL` and `B2B` when `<ANY_UNMAPPED>` was used instead of `<ANY_REMAINING>`.
+
+
+.Enum mapping method with `<THROW_EXCEPTION>`
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface SpecialOrderMapper {
+
+    SpecialOrderMapper INSTANCE = Mappers.getMapper( SpecialOrderMapper.class );
+
+    @ValueMappings({
+        @ValueMapping( source = "STANDARD", target = "DEFAULT" ),
+        @ValueMapping( source = "C2C", target = MappingConstants.THROW_EXCEPTION )
+    })
+    ExternalOrderType orderTypeToExternalOrderType(OrderType orderType);
+}
+----
+====
+
+.Enum mapping method with `<THROW_EXCEPTION>` result
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class SpecialOrderMapperImpl implements SpecialOrderMapper {
+
+    @Override
+    public ExternalOrderType orderTypeToExternalOrderType(OrderType orderType) {
+        if ( orderType == null ) {
+            return null;
+        }
+
+        ExternalOrderType externalOrderType;
+
+        switch ( orderType ) {
+            case STANDARD: externalOrderType = ExternalOrderType.DEFAULT;
+            break;
+            case C2C: throw new IllegalArgumentException( "Unexpected enum constant: " + orderType );
+            default: throw new IllegalArgumentException( "Unexpected enum constant: " + orderType );
+        }
+
+        return externalOrderType;
+    }
+}
+----
+====
+
+=== Mapping enum-to-String or String-to-enum
+
+MapStruct supports enum to a String mapping along the same lines as is described in <<Mapping enum to enum types, enum-to-enum types>>. There are similarities and differences:
+
+*enum to `String`*
+
+1. Similarity: All not explicit defined mappings will result in each source enum constant value being mapped a `String` value with the same constant value.
+2. Similarity: `<ANY_UNMAPPED`> stops after handling defined mapping and proceeds to the switch/default clause value.
+3. Difference: `<ANY_REMAINING>` will result in an error. It acts on the premise that there is name similarity between enum constants in source and target which does not make sense for a String type.
+4. Difference: Given 1. and 3. there will never be unmapped values.
+5. Similarity: `<THROW_EXCEPTION>` can be used for throwing an exception for particular enum values.
+
+*`String` to enum*
+
+1. Similarity: All not explicit defined mappings will result in the target enum constant mapped from the `String` value when that matches the target enum constant name.
+2. Similarity: `<ANY_UNMAPPED`> stops after handling defined mapping and proceeds to the switch/default clause value.
+3. Similarity: `<ANY_REMAINING>` will create a mapping for each target enum constant and proceed to the switch/default clause value.
+4. Difference: A switch/default value needs to be provided to have a determined outcome (enum has a limited set of values, `String` has unlimited options). Failing to specify `<ANY_REMAINING>` or `<ANY_UNMAPPED`> will result in a warning.
+5. Similarity: `<THROW_EXCEPTION>` can be used for throwing an exception for any arbitrary `String` value.
+
+=== Custom name transformation
+
+When no `@ValueMapping`(s) are defined then each constant from the source enum is mapped to a constant with the same name in the target enum type.
+However, there are cases where the source enum needs to be transformed before doing the mapping.
+E.g. a suffix needs to be applied to map from the source into the target enum.
+
+.Enum types
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public enum CheeseType {
+
+    BRIE,
+    ROQUEFORT
+}
+
+public enum CheeseTypeSuffixed {
+
+    BRIE_TYPE,
+    ROQUEFORT_TYPE
+}
+----
+====
+
+.Enum mapping method with custom name transformation strategy
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface CheeseMapper {
+
+    CheeseMapper INSTANCE = Mappers.getMapper( CheeseMapper.class );
+
+    @EnumMapping(nameTransformationStrategy = "suffix", configuration = "_TYPE")
+    CheeseTypeSuffixed map(CheeseType cheese);
+
+    @InheritInverseConfiguration
+    CheeseType map(CheeseTypeSuffix cheese);
+}
+----
+====
+
+.Enum mapping method with custom name transformation strategy result
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+// GENERATED CODE
+public class CheeseSuffixMapperImpl implements CheeseSuffixMapper {
+
+    @Override
+    public CheeseTypeSuffixed map(CheeseType cheese) {
+        if ( cheese == null ) {
+            return null;
+        }
+
+        CheeseTypeSuffixed cheeseTypeSuffixed;
+
+        switch ( cheese ) {
+            case BRIE: cheeseTypeSuffixed = CheeseTypeSuffixed.BRIE_TYPE;
+            break;
+            case ROQUEFORT: cheeseTypeSuffixed = CheeseTypeSuffixed.ROQUEFORT_TYPE;
+            break;
+            default: throw new IllegalArgumentException( "Unexpected enum constant: " + cheese );
+        }
+
+        return cheeseTypeSuffixed;
+    }
+
+    @Override
+    public CheeseType map(CheeseTypeSuffixed cheese) {
+        if ( cheese == null ) {
+            return null;
+        }
+
+        CheeseType cheeseType;
+
+        switch ( cheese ) {
+            case BRIE_TYPE: cheeseType = CheeseType.BRIE;
+            break;
+            case ROQUEFORT_TYPE: cheeseType = CheeseType.ROQUEFORT;
+            break;
+            default: throw new IllegalArgumentException( "Unexpected enum constant: " + cheese );
+        }
+
+        return cheeseType;
+    }
+}
+----
+====
+
+MapStruct provides the following out of the box enum name transformation strategies:
+
+* _suffix_ - Applies a suffix on the source enum
+* _stripSuffix_ - Strips a suffix from the source enum
+* _prefix_ - Applies a prefix on the source enum
+* _stripPrefix_ - Strips a prefix from the source enum
+* _case_ - Applies case transformation to the source enum. Supported _case_ transformations are:
+** _upper_ - Performs upper case transformation to the source enum
+** _lower_ - Performs lower case transformation to the source enum
+** _capital_ - Performs capitalisation of the first character of every word in the source enum and everything else to lowercase. A word is split by "_"
+
+It is also possible to register custom strategies.
+For more information on how to do that have a look at <<custom-enum-transformation-strategy>>
+
+[[value-mapping-composition]]
+=== ValueMapping Composition
+
+The `@ValueMapping` annotation supports now `@Target` with `ElementType#ANNOTATION_TYPE` in addition to `ElementType#METHOD`.
+This allows `@ValueMapping` to be used on other (user defined) annotations for re-use purposes.
+For example:
+
+.Custom value mapping annotations
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Retention( RetentionPolicy.CLASS )
+@ValueMapping(source = "EXTRA", target = "SPECIAL")
+@ValueMapping(source = MappingConstants.ANY_REMAINING, target = "DEFAULT")
+public @interface CustomValueAnnotation {
+}
+----
+====
+It can be used to describe some common value mapping relationships to avoid duplicate declarations, as in the following example:
+
+.Using custom combination annotations
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper
+public interface ValueMappingCompositionMapper {
+
+    @CustomValueAnnotation
+    ExternalOrderType orderTypeToExternalOrderType(OrderType orderType);
+
+    @CustomValueAnnotation
+    @ValueMapping(source = "STANDARD", target = "SPECIAL")
+    ExternalOrderType duplicateAnnotation(OrderType orderType);
+}
+----
+====

documentation/src/main/asciidoc/chapter-9-object-factories.asciidoc

@@ -0,0 +1,170 @@
+[[object-factories]]
+== Object factories
+
+By default, the generated code for mapping one bean type into another or updating a bean will call the default constructor to instantiate the target type.
+
+Alternatively you can plug in custom object factories which will be invoked to obtain instances of the target type. One use case for this is JAXB which creates `ObjectFactory` classes for obtaining new instances of schema types.
+
+To make use of custom factories register them via `@Mapper#uses()` as described in <<invoking-other-mappers>>, or implement them directly in your mapper. When creating the target object of a bean mapping, MapStruct will look for a parameterless method, a method annotated with `@ObjectFactory`, or a method with only one `@TargetType` parameter that returns the required target type and invoke this method instead of calling the default constructor:
+
+.Custom object factories
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class DtoFactory {
+
+     public CarDto createCarDto() {
+         return // ... custom factory logic
+     }
+}
+----
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class EntityFactory {
+
+     public <T extends BaseEntity> T createEntity(@TargetType Class<T> entityClass) {
+         return // ... custom factory logic
+     }
+}
+----
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper(uses= { DtoFactory.class, EntityFactory.class } )
+public interface CarMapper {
+
+    CarMapper INSTANCE = Mappers.getMapper( CarMapper.class );
+
+    CarDto carToCarDto(Car car);
+
+    Car carDtoToCar(CarDto carDto);
+}
+----
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+//GENERATED CODE
+public class CarMapperImpl implements CarMapper {
+
+    private final DtoFactory dtoFactory = new DtoFactory();
+
+    private final EntityFactory entityFactory = new EntityFactory();
+
+    @Override
+    public CarDto carToCarDto(Car car) {
+        if ( car == null ) {
+            return null;
+        }
+
+        CarDto carDto = dtoFactory.createCarDto();
+
+        //map properties...
+
+        return carDto;
+    }
+
+    @Override
+    public Car carDtoToCar(CarDto carDto) {
+        if ( carDto == null ) {
+            return null;
+        }
+
+        Car car = entityFactory.createEntity( Car.class );
+
+        //map properties...
+
+        return car;
+    }
+}
+----
+====
+
+.Custom object factories with update methods
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+@Mapper(uses = { DtoFactory.class, EntityFactory.class, CarMapper.class } )
+public interface OwnerMapper {
+
+    OwnerMapper INSTANCE = Mappers.getMapper( OwnerMapper.class );
+
+    void updateOwnerDto(Owner owner, @MappingTarget OwnerDto ownerDto);
+
+    void updateOwner(OwnerDto ownerDto, @MappingTarget Owner owner);
+}
+----
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+//GENERATED CODE
+public class OwnerMapperImpl implements OwnerMapper {
+
+    private final DtoFactory dtoFactory = new DtoFactory();
+
+    private final EntityFactory entityFactory = new EntityFactory();
+
+    private final OwnerMapper ownerMapper = Mappers.getMapper( OwnerMapper.class );
+
+    @Override
+    public void updateOwnerDto(Owner owner, @MappingTarget OwnerDto ownerDto) {
+        if ( owner == null ) {
+            return;
+        }
+
+        if ( owner.getCar() != null ) {
+            if ( ownerDto.getCar() == null ) {
+                ownerDto.setCar( dtoFactory.createCarDto() );
+            }
+            // update car within ownerDto
+        }
+        else {
+            ownerDto.setCar( null );
+        }
+
+       // updating other properties
+    }
+
+    @Override
+    public void updateOwner(OwnerDto ownerDto, @MappingTarget Owner owner) {
+        if ( ownerDto == null ) {
+            return;
+        }
+
+        if ( ownerDto.getCar() != null ) {
+            if ( owner.getCar() == null ) {
+                owner.setCar( entityFactory.createEntity( Car.class ) );
+            }
+            // update car within owner
+        }
+        else {
+            owner.setCar( null );
+        }
+
+       // updating other properties
+    }
+}
+----
+====
+
+In addition, annotating a factory method with `@ObjectFactory` lets you gain access to the mapping sources.
+Source objects can be added as parameters in the same way as for mapping method. The `@ObjectFactory`
+annotation is necessary to let MapStruct know that the given method is only a factory method.
+
+.Custom object factories with `@ObjectFactory`
+
+====
+[source, java, linenums]
+[subs="verbatim,attributes"]
+----
+public class DtoFactory {
+
+     @ObjectFactory
+     public CarDto createCarDto(Car car) {
+         return // ... custom factory logic
+     }
+}
+----
+====

documentation/src/main/asciidoc/controlling-nested-bean-mappings.asciidoc

@@ -1,89 +0,0 @@
-[[controlling-nested-bean-mappings]]
-=== Controlling nested bean mappings
-
-As explained above, MapStruct will generate a method based on the name of the source and target property. Unfortunately, in many occasions these names do not match.
-
-The ‘.’ notation in an `@Mapping` source or target type can be used to control how properties should be mapped when names do not match.
-There is an elaborate https://github.com/mapstruct/mapstruct-examples/tree/master/mapstruct-nested-bean-mappings[example] in our examples repository to explain how this problem can be overcome.
-
-In the simplest scenario there’s a property on a nested level that needs to be corrected.
-Take for instance a property `fish` which has an identical name in `FishTankDto` and `FishTank`.
-For this property MapStruct automatically generates a mapping: `FishDto fishToFishDto(Fish fish)`.
-MapStruct cannot possibly be aware of the deviating properties `kind` and `type`.
-Therefore this can be addressed in a mapping rule: `@Mapping(target="fish.kind", source="fish.type")`.
-This tells MapStruct to deviate from looking for a name `kind` at this level and map it to `type`.
-
-.Mapper controlling nested beans mappings I
-====
-[source, java, linenums]
-[subs="verbatim,attributes"]
-----
-@Mapper
-public interface FishTankMapper {
-
-    @Mapping(target = "fish.kind", source = "fish.type")
-    @Mapping(target = "fish.name", ignore = true)
-    @Mapping(target = "ornament", source = "interior.ornament")
-    @Mapping(target = "material.materialType", source = "material")
-    @Mapping(target = "quality.report.organisation.name", source = "quality.report.organisationName")
-    FishTankDto map( FishTank source );
-}
-----
-====
-
-The same constructs can be used to ignore certain properties at a nesting level, as is demonstrated in the second `@Mapping` rule.
-
-MapStruct can even be used to “cherry pick” properties when source and target do not share the same nesting level (the same number of properties).
-This can be done in the source – and in the target type. This is demonstrated in the next 2 rules: `@Mapping(target="ornament", source="interior.ornament")` and `@Mapping(target="material.materialType", source="material")`.
-
-The latter can even be done when mappings first share a common base.
-For example: all properties that share the same name of `Quality` are mapped to `QualityDto`.
-Likewise, all properties of `Report` are mapped to `ReportDto`, with one exception: `organisation` in `OrganisationDto` is left empty (since there is no organization at the source level).
-Only the `name` is populated with the `organisationName` from `Report`.
-This is demonstrated in `@Mapping(target="quality.report.organisation.name", source="quality.report.organisationName")`
-
-Coming back to the original example: what if `kind` and `type` would be beans themselves?
-In that case MapStruct would again generate a method continuing to map.
-Such is demonstrated in the next example:
-
-
-.Mapper controlling nested beans mappings II
-====
-[source, java, linenums]
-[subs="verbatim,attributes"]
-----
-@Mapper
-public interface FishTankMapperWithDocument {
-
-    @Mapping(target = "fish.kind", source = "fish.type")
-    @Mapping(target = "fish.name", expression = "java(\"Jaws\")")
-    @Mapping(target = "plant", ignore = true )
-    @Mapping(target = "ornament", ignore = true )
-    @Mapping(target = "material", ignore = true)
-    @Mapping(target = "quality.document", source = "quality.report")
-    @Mapping(target = "quality.document.organisation.name", constant = "NoIdeaInc" )
-    FishTankWithNestedDocumentDto map( FishTank source );
-
-}
-----
-====
-
-Note what happens in `@Mapping(target="quality.document", source="quality.report")`.
-`DocumentDto` does not exist as such on the target side. It is mapped from `Report`.
-MapStruct continues to generate mapping code here. That mapping itself can be guided towards another name.
-This even works for constants and expression. Which is shown in the final example: `@Mapping(target="quality.document.organisation.name", constant="NoIdeaInc")`.
-
-MapStruct will perform a null check on each nested property in the source.
-
-[TIP]
-====
-Instead of configuring everything via the parent method we encourage users to explicitly write their own nested methods.
-This puts the configuration of the nested mapping into one place (method) where it can be reused from several methods in the upper level,
-instead of re-configuring the same things on all of those upper methods.
-====
-
-[NOTE]
-====
-In some cases the `ReportingPolicy` that is going to be used for the generated nested method would be `IGNORE`.
-This means that it is possible for MapStruct not to report unmapped target properties in nested mappings.
-====

etc/toolchains-cloudbees-jenkins.xml

@@ -1,14 +0,0 @@
-<?xml version="1.0" encoding="UTF8"?>
-<toolchains>
-    <toolchain>
-        <type>jdk</type>
-        <provides>
-            <version>1.8</version>
-            <vendor>oracle</vendor>
-            <id>jdk1.8</id>
-        </provides>
-        <configuration>
-            <jdkHome>/opt/jdk/jdk8.latest</jdkHome>
-        </configuration>
-    </toolchain>
-</toolchains>

etc/toolchains-example.xml

@@ -1,25 +0,0 @@
-<?xml version="1.0" encoding="UTF8"?>
-<toolchains>
-    <toolchain>
-        <type>jdk</type>
-        <provides>
-            <version>1.8.0_11</version>
-            <vendor>oracle</vendor>
-            <id>jdk1.8</id>
-        </provides>
-        <configuration>
-            <jdkHome>C:\Program Files\Java\jdk1.8.0_11</jdkHome>
-        </configuration>
-    </toolchain>
-    <toolchain>
-        <type>jdk</type>
-        <provides>
-            <version>1.9.0</version>
-            <vendor>oracle</vendor>
-            <id>jdk1.9</id>
-        </provides>
-        <configuration>
-            <jdkHome>C:\Program Files\Java\jdk1.9.0</jdkHome>
-        </configuration>
-    </toolchain>
-</toolchains>

etc/toolchains-travis-jenkins.xml

@@ -1,16 +0,0 @@
-<?xml version="1.0" encoding="UTF8"?>
-<toolchains>
-
-    <toolchain>
-        <type>jdk</type>
-        <provides>
-            <version>1.8</version>
-            <vendor>oracle</vendor>
-            <id>jdk1.8</id>
-        </provides>
-        <configuration>
-            <jdkHome>/usr/lib/jvm/java-8-oracle/</jdkHome>
-        </configuration>
-    </toolchain>
-    
-</toolchains>

integrationtest/pom.xml

@@ -12,7 +12,7 @@
     <parent>
         <groupId>org.mapstruct</groupId>
         <artifactId>mapstruct-parent</artifactId>
-        <version>1.4.0-SNAPSHOT</version>
+        <version>1.7.0-SNAPSHOT</version>
         <relativePath>../parent/pom.xml</relativePath>
     </parent>
 
@@ -24,14 +24,22 @@
         <mapstruct.version>${project.version}</mapstruct.version>
         <maven.deploy.skip>true</maven.deploy.skip>
     </properties>
+    
+    <repositories>
+        <repository>
+            <id>gradle</id>
+            <url>https://repo.gradle.org/artifactory/libs-releases/</url>
+            <releases>
+                <enabled>true</enabled>
+            </releases>
+            <snapshots>
+                <enabled>false</enabled>
+            </snapshots>
+        </repository>
+    </repositories>
 
     <dependencies>
         <!-- Testing -->
-        <dependency>
-            <groupId>junit</groupId>
-            <artifactId>junit</artifactId>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
@@ -42,6 +50,34 @@
             <artifactId>maven-verifier</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.gradle</groupId>
+            <artifactId>gradle-test-kit</artifactId>
+            <version>5.6.4</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.gradle</groupId>
+            <artifactId>gradle-tooling-api</artifactId>
+            <version>5.6.4</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>commons-io</groupId>
+            <artifactId>commons-io</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <scope>test</scope>
+        </dependency>
+
     </dependencies>
 
     <build>
@@ -86,4 +122,21 @@
             </plugin>
         </plugins>
     </build>
+
+    <profiles>
+        <profile>
+            <id>jdk-11-or-newer</id>
+            <activation>
+                <jdk>[11</jdk>
+            </activation>
+            <dependencies>
+                <dependency>
+                    <groupId>javax.xml.bind</groupId>
+                    <artifactId>jaxb-api</artifactId>
+                    <scope>provided</scope>
+                    <optional>true</optional>
+                </dependency>
+            </dependencies>
+        </profile>
+    </profiles>
 </project>

integrationtest/src/test/java/org/mapstruct/itest/tests/AutoValueBuilderTest.java

@@ -1,19 +0,0 @@
-/*
- * Copyright MapStruct Authors.
- *
- * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
- */
-package org.mapstruct.itest.tests;
-
-import org.junit.runner.RunWith;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite;
-import org.mapstruct.itest.testutil.runner.ProcessorSuiteRunner;
-
-/**
- * @author Filip Hrisafov
- */
-@RunWith( ProcessorSuiteRunner.class )
-@ProcessorSuite(baseDir = "autoValueBuilderTest",
-    processorTypes = ProcessorSuite.ProcessorType.ALL_WITHOUT_PROCESSOR_PLUGIN)
-public class AutoValueBuilderTest {
-}

integrationtest/src/test/java/org/mapstruct/itest/tests/CdiTest.java

@@ -1,20 +0,0 @@
-/*
- * Copyright MapStruct Authors.
- *
- * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
- */
-package org.mapstruct.itest.tests;
-
-import org.junit.runner.RunWith;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite.ProcessorType;
-import org.mapstruct.itest.testutil.runner.ProcessorSuiteRunner;
-
-/**
- * @author Andreas Gudian
- *
- */
-@RunWith( ProcessorSuiteRunner.class )
-@ProcessorSuite( baseDir = "cdiTest", processorTypes = ProcessorType.ALL )
-public class CdiTest {
-}

integrationtest/src/test/java/org/mapstruct/itest/tests/ExternalBeanJarTest.java

@@ -1,22 +0,0 @@
-/*
- * Copyright MapStruct Authors.
- *
- * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
- */
-package org.mapstruct.itest.tests;
-
-import org.junit.runner.RunWith;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite;
-import org.mapstruct.itest.testutil.runner.ProcessorSuiteRunner;
-
-/**
- *
- * See: https://github.com/mapstruct/mapstruct/issues/1121
- *
- * @author Sjaak Derksen
- */
-@RunWith( ProcessorSuiteRunner.class )
-@ProcessorSuite(baseDir = "externalbeanjar", processorTypes = ProcessorSuite.ProcessorType.ORACLE_JAVA_8)
-public class ExternalBeanJarTest {
-
-}

integrationtest/src/test/java/org/mapstruct/itest/tests/FreeBuilderBuilderTest.java

@@ -1,19 +0,0 @@
-/*
- * Copyright MapStruct Authors.
- *
- * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
- */
-package org.mapstruct.itest.tests;
-
-import org.junit.runner.RunWith;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite;
-import org.mapstruct.itest.testutil.runner.ProcessorSuiteRunner;
-
-/**
- * @author Filip Hrisafov
- */
-@RunWith( ProcessorSuiteRunner.class )
-@ProcessorSuite( baseDir = "freeBuilderBuilderTest",
-    processorTypes = ProcessorSuite.ProcessorType.ALL_WITHOUT_PROCESSOR_PLUGIN)
-public class FreeBuilderBuilderTest {
-}

integrationtest/src/test/java/org/mapstruct/itest/tests/FullFeatureCompilationExclusionCliEnhancer.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.itest.tests;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+import org.junit.jupiter.api.condition.JRE;
+import org.mapstruct.itest.testutil.extension.ProcessorTest;
+
+/**
+ * Adds explicit exclusions of test mappers that are known or expected to not work with specific compilers.
+ *
+ * @author Andreas Gudian
+ */
+public final class FullFeatureCompilationExclusionCliEnhancer implements ProcessorTest.CommandLineEnhancer {
+    @Override
+    public Collection<String> getAdditionalCommandLineArguments(ProcessorTest.ProcessorType processorType,
+        JRE currentJreVersion) {
+        List<String> additionalExcludes = new ArrayList<>();
+
+        // SPI not working correctly here.. (not picked up)
+        additionalExcludes.add( "org/mapstruct/ap/test/bugs/_1596/*.java" );
+        additionalExcludes.add( "org/mapstruct/ap/test/bugs/_1801/*.java" );
+        additionalExcludes.add( "org/mapstruct/ap/test/bugs/_3089/*.java" );
+
+        switch ( currentJreVersion ) {
+            case JAVA_8:
+                additionalExcludes.add( "org/mapstruct/ap/test/**/spring/**/*.java" );
+                additionalExcludes.add( "org/mapstruct/ap/test/injectionstrategy/cdi/**/*.java" );
+                additionalExcludes.add( "org/mapstruct/ap/test/injectionstrategy/jakarta_cdi/**/*.java" );
+                additionalExcludes.add( "org/mapstruct/ap/test/annotatewith/deprecated/jdk11/*.java" );
+                additionalExcludes.add( "org/mapstruct/ap/test/**/jdk21/*.java" );
+                if ( processorType == ProcessorTest.ProcessorType.ECLIPSE_JDT ) {
+                    additionalExcludes.add(
+                        "org/mapstruct/ap/test/selection/methodgenerics/wildcards/LifecycleIntersectionMapper.java" );
+                }
+                break;
+            case JAVA_9:
+                // TODO find out why this fails:
+                additionalExcludes.add( "org/mapstruct/ap/test/collection/wildcard/BeanMapper.java" );
+                additionalExcludes.add( "org/mapstruct/ap/test/**/jdk21/*.java" );
+                break;
+            case JAVA_11:
+                additionalExcludes.add( "org/mapstruct/ap/test/**/spring/**/*.java" );
+                additionalExcludes.add( "org/mapstruct/ap/test/**/jdk21/*.java" );
+                break;
+            case JAVA_17:
+                additionalExcludes.add( "org/mapstruct/ap/test/**/jdk21/*.java" );
+                break;
+            default:
+        }
+
+        Collection<String> result = new ArrayList<>(additionalExcludes.size());
+        for ( int i = 0; i < additionalExcludes.size(); i++ ) {
+            result.add( "-DadditionalExclude" + i + "=" + additionalExcludes.get( i ) );
+        }
+
+        return result;
+    }
+}

integrationtest/src/test/java/org/mapstruct/itest/tests/FullFeatureCompilationTest.java

@@ -1,71 +0,0 @@
-/*
- * Copyright MapStruct Authors.
- *
- * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
- */
-package org.mapstruct.itest.tests;
-
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.List;
-
-import org.junit.runner.RunWith;
-import org.mapstruct.itest.tests.FullFeatureCompilationTest.CompilationExclusionCliEnhancer;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite.CommandLineEnhancer;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite.ProcessorType;
-import org.mapstruct.itest.testutil.runner.ProcessorSuiteRunner;
-
-/**
- * Integration test that compiles all test mappers in the processor-module, excluding all classes that contain one of
- * the following in their path/file name:
- * <ul>
- * <li>{@code /erronerous/}</li>
- * <li>{@code *Erroneous*}</li>
- * <li>{@code *Test.java}</li>
- * <li>{@code /testutil/}</li>
- * <li>possibly more, depending on the processor type - see {@link CompilationExclusionCliEnhancer}</li>
- * </ul>
- *
- * @author Andreas Gudian
- */
-@RunWith(ProcessorSuiteRunner.class)
-@ProcessorSuite(
-    baseDir = "fullFeatureTest",
-    commandLineEnhancer = CompilationExclusionCliEnhancer.class,
-    processorTypes = {
-        ProcessorType.ORACLE_JAVA_8,
-        ProcessorType.ORACLE_JAVA_9,
-        ProcessorType.ECLIPSE_JDT_JAVA_8
-})
-public class FullFeatureCompilationTest {
-    /**
-     * Adds explicit exclusions of test mappers that are known or expected to not work with specific compilers.
-     *
-     * @author Andreas Gudian
-     */
-    public static final class CompilationExclusionCliEnhancer implements CommandLineEnhancer {
-        @Override
-        public Collection<String> getAdditionalCommandLineArguments(ProcessorType processorType) {
-            List<String> additionalExcludes = new ArrayList<>();
-
-            // SPI not working correctly here.. (not picked up)
-            additionalExcludes.add( "org/mapstruct/ap/test/bugs/_1596/*.java" );
-
-            switch ( processorType ) {
-                case ORACLE_JAVA_9:
-                    // TODO find out why this fails:
-                    additionalExcludes.add( "org/mapstruct/ap/test/collection/wildcard/BeanMapper.java" );
-                    break;
-                default:
-            }
-
-            Collection<String> result = new ArrayList<String>( additionalExcludes.size() );
-            for ( int i = 0; i < additionalExcludes.size(); i++ ) {
-                result.add( "-DadditionalExclude" + i + "=" + additionalExcludes.get( i ) );
-            }
-
-            return result;
-        }
-    }
-}

integrationtest/src/test/java/org/mapstruct/itest/tests/GradleIncrementalCompilationTest.java

@@ -0,0 +1,170 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.itest.tests;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import org.apache.commons.io.FileUtils;
+import org.gradle.testkit.runner.BuildResult;
+import org.gradle.testkit.runner.GradleRunner;
+import org.gradle.testkit.runner.TaskOutcome;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.condition.DisabledForJreRange;
+import org.junit.jupiter.api.condition.JRE;
+import org.junit.jupiter.api.io.TempDir;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import org.junit.runners.Parameterized.Parameters;
+
+import static org.gradle.testkit.runner.TaskOutcome.SUCCESS;
+import static org.gradle.testkit.runner.TaskOutcome.UP_TO_DATE;
+import static org.hamcrest.core.StringContains.containsString;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThat;
+
+/**
+ * <p>This is supposed to be run from the mapstruct root project folder.
+ * Otherwise, use <code>-Dmapstruct_root=path_to_project</code>.
+ */
+@DisabledForJreRange(min = JRE.JAVA_11)
+public class GradleIncrementalCompilationTest {
+    private static Path rootPath;
+    private static String projectDir = "integrationtest/src/test/resources/gradleIncrementalCompilationTest";
+    private static String compileTaskName = "compileJava";
+
+    @TempDir
+    File testBuildDir;
+    @TempDir
+    File testProjectDir;
+
+    private GradleRunner runner;
+    private File sourceDirectory;
+    private List<String> compileArgs; // Gradle compile task arguments
+
+    @Parameters(name = "Gradle {0}")
+    public static List<String> gradleVersions() {
+        return Arrays.asList( "5.0", "6.0" );
+    }
+
+    private void replaceInFile(File file, CharSequence target, CharSequence replacement) throws IOException {
+        String content = FileUtils.readFileToString( file, Charset.defaultCharset() );
+        FileUtils.writeStringToFile( file, content.replace( target, replacement ), Charset.defaultCharset() );
+    }
+
+    private GradleRunner getRunner(String... additionalArguments) {
+        List<String> fullArguments = new ArrayList<>(compileArgs);
+        fullArguments.addAll( Arrays.asList( additionalArguments ) );
+        return runner.withArguments( fullArguments );
+    }
+
+    private void assertCompileOutcome(BuildResult result, TaskOutcome outcome) {
+        assertEquals( outcome, result.task( ":" + compileTaskName ).getOutcome() );
+    }
+
+    private void assertRecompiled(BuildResult result, int recompiledCount) {
+        assertCompileOutcome( result, recompiledCount > 0 ? SUCCESS : UP_TO_DATE );
+        assertThat(
+            result.getOutput(),
+            containsString( String.format( "Incremental compilation of %d classes completed", recompiledCount ) )
+        );
+    }
+
+    private List<String> buildCompileArgs() {
+        // Make Gradle use the temporary build folder by overriding the buildDir property
+        String buildDirPropertyArg = "-PbuildDir=" + testBuildDir.getAbsolutePath();
+
+        // Inject the path to the folder containing the mapstruct-processor JAR
+        String jarDirectoryArg = "-PmapstructRootPath=" + rootPath.toString();
+        return Arrays.asList( compileTaskName, buildDirPropertyArg, jarDirectoryArg );
+    }
+
+    @BeforeAll
+    public static void setupClass() throws Exception {
+        rootPath = Paths.get( System.getProperty( "mapstruct_root", "." ) ).toAbsolutePath();
+    }
+
+    public void setup(String gradleVersion) throws IOException {
+        if ( !testBuildDir.exists() ) {
+            testBuildDir.mkdirs();
+        }
+
+        if ( !testProjectDir.exists() ) {
+            testProjectDir.mkdirs();
+        }
+        // Copy test project files to the temp dir
+        Path gradleProjectPath = rootPath.resolve( projectDir );
+        FileUtils.copyDirectory( gradleProjectPath.toFile(), testProjectDir );
+        compileArgs = buildCompileArgs();
+        sourceDirectory = new File( testProjectDir, "src/main/java" );
+        runner = GradleRunner.create().withGradleVersion( gradleVersion ).withProjectDir( testProjectDir );
+    }
+
+    @ParameterizedTest
+    @MethodSource("gradleVersions")
+    public void testBuildSucceeds(String gradleVersion) throws IOException {
+        setup( gradleVersion );
+        // Make sure the test build setup actually compiles
+        BuildResult buildResult = getRunner().build();
+        assertCompileOutcome( buildResult, SUCCESS );
+    }
+
+    @ParameterizedTest
+    @MethodSource("gradleVersions")
+    public void testUpToDate(String gradleVersion) throws IOException {
+        setup( gradleVersion );
+        getRunner().build();
+        BuildResult secondBuildResult = getRunner().build();
+        assertCompileOutcome( secondBuildResult, UP_TO_DATE );
+    }
+
+    @ParameterizedTest
+    @MethodSource("gradleVersions")
+    public void testChangeConstant(String gradleVersion) throws IOException {
+        setup( gradleVersion );
+        getRunner().build();
+        // Change return value in class Target
+        File targetFile = new File( sourceDirectory, "org/mapstruct/itest/gradle/model/Target.java" );
+        replaceInFile( targetFile, "original", "changed" );
+        BuildResult secondBuildResult = getRunner( "--info" ).build();
+
+        // 3 classes should be recompiled: Target -> TestMapper -> TestMapperImpl
+        assertRecompiled( secondBuildResult, 3 );
+    }
+
+    @ParameterizedTest
+    @MethodSource("gradleVersions")
+    public void testChangeTargetField(String gradleVersion) throws IOException {
+        setup( gradleVersion );
+        getRunner().build();
+        // Change target field in mapper interface
+        File mapperFile = new File( sourceDirectory, "org/mapstruct/itest/gradle/lib/TestMapper.java" );
+        replaceInFile( mapperFile, "field", "otherField" );
+        BuildResult secondBuildResult = getRunner( "--info" ).build();
+
+        // 2 classes should be recompiled: TestMapper -> TestMapperImpl
+        assertRecompiled( secondBuildResult, 2 );
+    }
+
+    @ParameterizedTest
+    @MethodSource("gradleVersions")
+    public void testChangeUnrelatedFile(String gradleVersion) throws IOException {
+        setup( gradleVersion );
+        getRunner().build();
+        File unrelatedFile = new File( sourceDirectory, "org/mapstruct/itest/gradle/lib/UnrelatedComponent.java" );
+        replaceInFile( unrelatedFile, "true", "false" );
+        BuildResult secondBuildResult = getRunner( "--info" ).build();
+
+        // Only the UnrelatedComponent class should be recompiled
+        assertRecompiled( secondBuildResult, 1 );
+    }
+}

integrationtest/src/test/java/org/mapstruct/itest/tests/ImmutablesBuilderTest.java

@@ -1,19 +0,0 @@
-/*
- * Copyright MapStruct Authors.
- *
- * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
- */
-package org.mapstruct.itest.tests;
-
-import org.junit.runner.RunWith;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite;
-import org.mapstruct.itest.testutil.runner.ProcessorSuiteRunner;
-
-/**
- * @author Filip Hrisafov
- */
-@RunWith( ProcessorSuiteRunner.class )
-@ProcessorSuite( baseDir = "immutablesBuilderTest",
-    processorTypes = ProcessorSuite.ProcessorType.ALL_WITHOUT_PROCESSOR_PLUGIN)
-public class ImmutablesBuilderTest {
-}

integrationtest/src/test/java/org/mapstruct/itest/tests/Java8Test.java

@@ -1,20 +0,0 @@
-/*
- * Copyright MapStruct Authors.
- *
- * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
- */
-package org.mapstruct.itest.tests;
-
-import org.junit.runner.RunWith;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite.ProcessorType;
-import org.mapstruct.itest.testutil.runner.ProcessorSuiteRunner;
-
-/**
- * @author Andreas Gudian
- *
- */
-@RunWith( ProcessorSuiteRunner.class )
-@ProcessorSuite( baseDir = "java8Test", processorTypes = ProcessorType.ALL_JAVA_8 )
-public class Java8Test {
-}

integrationtest/src/test/java/org/mapstruct/itest/tests/JaxbTest.java

@@ -1,20 +0,0 @@
-/*
- * Copyright MapStruct Authors.
- *
- * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
- */
-package org.mapstruct.itest.tests;
-
-import org.junit.runner.RunWith;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite.ProcessorType;
-import org.mapstruct.itest.testutil.runner.ProcessorSuiteRunner;
-
-/**
- * @author Andreas Gudian
- *
- */
-@RunWith( ProcessorSuiteRunner.class )
-@ProcessorSuite( baseDir = "jaxbTest", processorTypes = ProcessorType.ALL )
-public class JaxbTest {
-}

integrationtest/src/test/java/org/mapstruct/itest/tests/Jsr330Test.java

@@ -1,20 +0,0 @@
-/*
- * Copyright MapStruct Authors.
- *
- * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
- */
-package org.mapstruct.itest.tests;
-
-import org.junit.runner.RunWith;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite;
-import org.mapstruct.itest.testutil.runner.ProcessorSuite.ProcessorType;
-import org.mapstruct.itest.testutil.runner.ProcessorSuiteRunner;
-
-/**
- * @author Andreas Gudian
- *
- */
-@RunWith( ProcessorSuiteRunner.class )
-@ProcessorSuite( baseDir = "jsr330Test", processorTypes = ProcessorType.ALL )
-public class Jsr330Test {
-}