#424 Add Compiler implementation info to @Generated#comment

processor/src/main/java/org/mapstruct/ap/MappingProcessor.java

@@ -83,6 +83,7 @@ import org.mapstruct.ap.util.AnnotationProcessingException;
 @SupportedAnnotationTypes("org.mapstruct.Mapper")
 @SupportedOptions({
     MappingProcessor.SUPPRESS_GENERATOR_TIMESTAMP,
+    MappingProcessor.SUPPRESS_GENERATOR_VERSION_INFO_COMMENT,
     MappingProcessor.UNMAPPED_TARGET_POLICY,
     MappingProcessor.DEFAULT_COMPONENT_MODEL
 })
@@ -94,6 +95,8 @@ public class MappingProcessor extends AbstractProcessor {
     private static final boolean ANNOTATIONS_CLAIMED_EXCLUSIVELY = false;
 
     protected static final String SUPPRESS_GENERATOR_TIMESTAMP = "mapstruct.suppressGeneratorTimestamp";
+    protected static final String SUPPRESS_GENERATOR_VERSION_INFO_COMMENT =
+        "mapstruct.suppressGeneratorVersionInfoComment";
     protected static final String UNMAPPED_TARGET_POLICY = "mapstruct.unmappedTargetPolicy";
     protected static final String DEFAULT_COMPONENT_MODEL = "mapstruct.defaultComponentModel";
 
@@ -111,6 +114,7 @@ public class MappingProcessor extends AbstractProcessor {
 
         return new Options(
             Boolean.valueOf( processingEnv.getOptions().get( SUPPRESS_GENERATOR_TIMESTAMP ) ),
+            Boolean.valueOf( processingEnv.getOptions().get( SUPPRESS_GENERATOR_VERSION_INFO_COMMENT ) ),
             unmappedTargetPolicy != null ? ReportingPolicy.valueOf( unmappedTargetPolicy ) : null,
             processingEnv.getOptions().get( DEFAULT_COMPONENT_MODEL )
         );

processor/src/main/java/org/mapstruct/ap/model/Decorator.java

@@ -21,14 +21,18 @@ package org.mapstruct.ap.model;
 import java.util.Arrays;
 import java.util.List;
 import java.util.TreeSet;
+
 import javax.lang.model.element.ElementKind;
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.util.Elements;
+
 import org.mapstruct.ap.model.common.Accessibility;
 import org.mapstruct.ap.model.common.ModelElement;
 import org.mapstruct.ap.model.common.Type;
 import org.mapstruct.ap.model.common.TypeFactory;
+import org.mapstruct.ap.option.Options;
 import org.mapstruct.ap.prism.DecoratedWithPrism;
+import org.mapstruct.ap.version.VersionInformation;
 
 /**
  * Represents a decorator applied to a generated mapper type.
@@ -41,7 +45,7 @@ public class Decorator extends GeneratedType {
 
     private Decorator(TypeFactory typeFactory, String packageName, String name, String superClassName,
                       String interfaceName, List<MappingMethod> methods, List<? extends ModelElement> fields,
-                      boolean suppressGeneratorTimestamp, Accessibility accessibility ) {
+                      Options options, VersionInformation versionInformation, Accessibility accessibility) {
         super(
             typeFactory,
             packageName,
@@ -50,7 +54,8 @@ public class Decorator extends GeneratedType {
             interfaceName,
             methods,
             fields,
-            suppressGeneratorTimestamp,
+            options,
+            versionInformation,
             accessibility,
             new TreeSet<Type>()
         );
@@ -58,8 +63,8 @@ public class Decorator extends GeneratedType {
 
     public static Decorator getInstance(Elements elementUtils, TypeFactory typeFactory, TypeElement mapperElement,
                                         DecoratedWithPrism decoratorPrism, List<MappingMethod> methods,
-                                        boolean hasDelegateConstructor,
+                                        boolean hasDelegateConstructor, Options options,
-                                        boolean suppressGeneratorTimestamp) {
+                                        VersionInformation versionInformation) {
         Type decoratorType = typeFactory.getType( decoratorPrism.value() );
 
         return new Decorator(
@@ -77,7 +82,8 @@ public class Decorator extends GeneratedType {
                     hasDelegateConstructor
                 )
             ),
-            suppressGeneratorTimestamp,
+            options,
+            versionInformation,
             Accessibility.fromModifiers( mapperElement.getModifiers() )
         );
     }

processor/src/main/java/org/mapstruct/ap/model/GeneratedType.java

@@ -18,21 +18,20 @@
  */
 package org.mapstruct.ap.model;
 
-import java.io.IOException;
-import java.net.URL;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Enumeration;
 import java.util.List;
 import java.util.SortedSet;
 import java.util.TreeSet;
-import java.util.jar.Manifest;
+
 import javax.annotation.Generated;
 
 import org.mapstruct.ap.model.common.Accessibility;
 import org.mapstruct.ap.model.common.ModelElement;
 import org.mapstruct.ap.model.common.Type;
 import org.mapstruct.ap.model.common.TypeFactory;
+import org.mapstruct.ap.option.Options;
+import org.mapstruct.ap.version.VersionInformation;
 
 /**
  * A type generated by MapStruct, e.g. representing a mapper type.
@@ -41,9 +40,6 @@ import org.mapstruct.ap.model.common.TypeFactory;
  */
 public abstract class GeneratedType extends ModelElement {
 
-    private static final String COMMENT_TAG = "Implementation-Version";
-    private static final String COMMENTS = initComment();
-
     private final String packageName;
     private final String name;
     private final String superClassName;
@@ -55,6 +51,8 @@ public abstract class GeneratedType extends ModelElement {
     private final SortedSet<Type> extraImportedTypes;
 
     private final boolean suppressGeneratorTimestamp;
+    private final boolean suppressGeneratorVersionComment;
+    private final VersionInformation versionInformation;
     private final Accessibility accessibility;
 
     /**
@@ -62,11 +60,13 @@ public abstract class GeneratedType extends ModelElement {
      */
     private final Type generatedType;
 
+    // CHECKSTYLE:OFF
     protected GeneratedType(TypeFactory typeFactory, String packageName, String name, String superClassName,
                             String interfaceName,
                             List<MappingMethod> methods,
                             List<? extends ModelElement> fields,
-                            boolean suppressGeneratorTimestamp,
+                            Options options,
+                            VersionInformation versionInformation,
                             Accessibility accessibility,
                             SortedSet<Type> extraImportedTypes) {
         this.packageName = packageName;
@@ -79,12 +79,16 @@ public abstract class GeneratedType extends ModelElement {
         this.methods = methods;
         this.fields = fields;
 
-        this.suppressGeneratorTimestamp = suppressGeneratorTimestamp;
+        this.suppressGeneratorTimestamp = options.isSuppressGeneratorTimestamp();
+        this.suppressGeneratorVersionComment = options.isSuppressGeneratorVersionComment();
+        this.versionInformation = versionInformation;
         this.accessibility = accessibility;
 
         this.generatedType = typeFactory.getType( Generated.class );
     }
 
+    // CHECKSTYLE:ON
+
     public String getPackageName() {
         return packageName;
     }
@@ -121,12 +125,16 @@ public abstract class GeneratedType extends ModelElement {
         return suppressGeneratorTimestamp;
     }
 
-    public Accessibility getAccessibility() {
+    public boolean isSuppressGeneratorVersionComment() {
-        return accessibility;
+        return suppressGeneratorVersionComment;
     }
 
-    public String getComments() {
+    public VersionInformation getVersionInformation() {
-        return COMMENTS;
+        return versionInformation;
+    }
+
+    public Accessibility getAccessibility() {
+        return accessibility;
     }
 
     @Override
@@ -179,23 +187,4 @@ public abstract class GeneratedType extends ModelElement {
             addWithDependents( collection, type );
         }
     }
-
-    private static String initComment() {
-        String result = null;
-        try {
-            Enumeration<URL> resources = GeneratedType.class.getClassLoader().getResources( "META-INF/MANIFEST.MF" );
-            while ( resources.hasMoreElements() ) {
-                Manifest manifest = new Manifest( resources.nextElement().openStream() );
-                String resultValue = manifest.getMainAttributes().getValue( COMMENT_TAG );
-                if (resultValue != null ) {
-                    result = COMMENT_TAG + ": " + resultValue;
-                    break;
-                }
-            }
-        }
-        catch ( IOException ex ) {
-            return result;
-        }
-        return result;
-    }
 }

processor/src/main/java/org/mapstruct/ap/model/Mapper.java

@@ -20,12 +20,16 @@ package org.mapstruct.ap.model;
 
 import java.util.List;
 import java.util.SortedSet;
+
 import javax.lang.model.element.ElementKind;
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.util.Elements;
+
 import org.mapstruct.ap.model.common.Accessibility;
 import org.mapstruct.ap.model.common.Type;
 import org.mapstruct.ap.model.common.TypeFactory;
+import org.mapstruct.ap.option.Options;
+import org.mapstruct.ap.version.VersionInformation;
 
 /**
  * Represents a type implementing a mapper interface (annotated with {@code @Mapper}). This is the root object of the
@@ -41,10 +45,11 @@ public class Mapper extends GeneratedType {
     private final List<MapperReference> referencedMappers;
     private final Decorator decorator;
 
-    //CHECKSTYLE:OFF
+    @SuppressWarnings( "checkstyle:parameternumber" )
     private Mapper(TypeFactory typeFactory, String packageName, String name, String superClassName,
-                   String interfaceName, List<MappingMethod> methods, boolean suppressGeneratorTimestamp,
+                   String interfaceName, List<MappingMethod> methods, Options options,
-                   Accessibility accessibility, List<MapperReference> referencedMappers, Decorator decorator,
+                   VersionInformation versionInformation, Accessibility accessibility,
+                   List<MapperReference> referencedMappers, Decorator decorator,
                    SortedSet<Type> extraImportedTypes ) {
 
         super(
@@ -55,7 +60,8 @@ public class Mapper extends GeneratedType {
             interfaceName,
             methods,
             referencedMappers,
-            suppressGeneratorTimestamp,
+            options,
+            versionInformation,
             accessibility,
             extraImportedTypes
         );
@@ -73,7 +79,8 @@ public class Mapper extends GeneratedType {
         private SortedSet<Type> extraImportedTypes;
 
         private Elements elementUtils;
-        private boolean suppressGeneratorTimestamp;
+        private Options options;
+        private VersionInformation versionInformation;
         private Decorator decorator;
 
         public Builder element(TypeElement element) {
@@ -91,8 +98,13 @@ public class Mapper extends GeneratedType {
             return this;
         }
 
-        public Builder suppressGeneratorTimestamp(boolean suppressGeneratorTimestamp) {
+        public Builder options(Options options) {
-            this.suppressGeneratorTimestamp = suppressGeneratorTimestamp;
+            this.options = options;
+            return this;
+        }
+
+        public Builder versionInformation(VersionInformation versionInformation) {
+            this.versionInformation = versionInformation;
             return this;
         }
 
@@ -127,7 +139,8 @@ public class Mapper extends GeneratedType {
                 element.getKind() != ElementKind.INTERFACE ? element.getSimpleName().toString() : null,
                 element.getKind() == ElementKind.INTERFACE ? element.getSimpleName().toString() : null,
                 mappingMethods,
-                suppressGeneratorTimestamp,
+                options,
+                versionInformation,
                 Accessibility.fromModifiers( element.getModifiers() ),
                 mapperReferences,
                 decorator,

processor/src/main/java/org/mapstruct/ap/option/Options.java

@@ -27,12 +27,15 @@ package org.mapstruct.ap.option;
  */
 public class Options {
     private final boolean suppressGeneratorTimestamp;
+    private final boolean suppressGeneratorVersionComment;
     private final ReportingPolicy unmappedTargetPolicy;
     private final String defaultComponentModel;
 
-    public Options(boolean suppressGeneratorTimestamp, ReportingPolicy unmappedTargetPolicy,
+    public Options(boolean suppressGeneratorTimestamp, boolean suppressGeneratorVersionComment,
+                   ReportingPolicy unmappedTargetPolicy,
                    String defaultComponentModel) {
         this.suppressGeneratorTimestamp = suppressGeneratorTimestamp;
+        this.suppressGeneratorVersionComment = suppressGeneratorVersionComment;
         this.unmappedTargetPolicy = unmappedTargetPolicy;
         this.defaultComponentModel = defaultComponentModel;
     }
@@ -41,6 +44,10 @@ public class Options {
         return suppressGeneratorTimestamp;
     }
 
+    public boolean isSuppressGeneratorVersionComment() {
+        return suppressGeneratorVersionComment;
+    }
+
     public ReportingPolicy getUnmappedTargetPolicy() {
         return unmappedTargetPolicy;
     }

processor/src/main/java/org/mapstruct/ap/processor/DefaultModelElementProcessorContext.java

@@ -30,18 +30,21 @@ import javax.tools.Diagnostic.Kind;
 
 import org.mapstruct.ap.model.common.TypeFactory;
 import org.mapstruct.ap.option.Options;
+import org.mapstruct.ap.processor.ModelElementProcessor.ProcessorContext;
+import org.mapstruct.ap.version.VersionInformation;
 
 /**
  * Default implementation of the processor context.
  *
  * @author Gunnar Morling
  */
-public class DefaultModelElementProcessorContext implements ModelElementProcessor.ProcessorContext {
+public class DefaultModelElementProcessorContext implements ProcessorContext {
 
     private final ProcessingEnvironment processingEnvironment;
     private final DelegatingMessager messager;
     private final Options options;
     private final TypeFactory typeFactory;
+    private final VersionInformation versionInformation;
 
     public DefaultModelElementProcessorContext(ProcessingEnvironment processingEnvironment, Options options) {
         this.processingEnvironment = processingEnvironment;
@@ -51,6 +54,7 @@ public class DefaultModelElementProcessorContext implements ModelElementProcesso
             processingEnvironment.getTypeUtils()
         );
         this.options = options;
+        this.versionInformation = DefaultVersionInformation.fromProcessingEnvironment( processingEnvironment );
     }
 
     @Override
@@ -83,6 +87,11 @@ public class DefaultModelElementProcessorContext implements ModelElementProcesso
         return options;
     }
 
+    @Override
+    public VersionInformation getVersionInformation() {
+        return versionInformation;
+    }
+
     @Override
     public boolean isErroneous() {
         return messager.isErroneous();

processor/src/main/java/org/mapstruct/ap/processor/DefaultVersionInformation.java

@@ -0,0 +1,199 @@
+/**
+ *  Copyright 2012-2015 Gunnar Morling (http://www.gunnarmorling.de/)
+ *  and/or other contributors as indicated by the @authors tag. See the
+ *  copyright.txt file in the distribution for a full listing of all
+ *  contributors.
+ *
+ *  Licensed 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.
+ */
+package org.mapstruct.ap.processor;
+
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.jar.Manifest;
+
+import javax.annotation.processing.ProcessingEnvironment;
+
+import org.mapstruct.ap.version.VersionInformation;
+
+/**
+ * Provides information about the processor version and the processor context implementation version.
+ * <p>
+ * Separated into an interface and this implementation to avoid cyclic dependencies between the processor package and
+ * the model package.
+ *
+ * @author Andreas Gudian
+ */
+public class DefaultVersionInformation implements VersionInformation {
+    private static final String JAVAC_PE_CLASS = "com.sun.tools.javac.processing.JavacProcessingEnvironment";
+    private static final String JDT_IDE_PE_CLASS =
+        "org.eclipse.jdt.internal.apt.pluggable.core.dispatch.IdeBuildProcessingEnvImpl";
+    private static final String JDT_BATCH_PE_CLASS =
+        "org.eclipse.jdt.internal.compiler.apt.dispatch.BatchProcessingEnvImpl";
+
+    private static final String MAP_STRUCT_VERSION = initMapStructVersion();
+
+    private final String runtimeVersion;
+    private final String runtimeVendor;
+    private final String compiler;
+
+    DefaultVersionInformation(String runtimeVersion, String runtimeVendor, String compiler) {
+        this.runtimeVersion = runtimeVersion;
+        this.runtimeVendor = runtimeVendor;
+        this.compiler = compiler;
+    }
+
+    @Override
+    public String getRuntimeVersion() {
+        return this.runtimeVersion;
+    }
+
+    @Override
+    public String getRuntimeVendor() {
+        return this.runtimeVendor;
+    }
+
+    @Override
+    public String getMapStructVersion() {
+        return MAP_STRUCT_VERSION;
+    }
+
+    @Override
+    public String getCompiler() {
+        return this.compiler;
+    }
+
+    static DefaultVersionInformation fromProcessingEnvironment(ProcessingEnvironment processingEnv) {
+        String runtimeVersion = System.getProperty( "java.version" );
+        String runtimeVendor = System.getProperty( "java.vendor" );
+
+        String compiler = getCompiler( processingEnv );
+
+        return new DefaultVersionInformation( runtimeVersion, runtimeVendor, compiler );
+    }
+
+    private static String getCompiler(ProcessingEnvironment processingEnv) {
+        String className = processingEnv.getClass().getName();
+
+        if ( className.equals( JAVAC_PE_CLASS ) ) {
+            return "javac";
+        }
+
+        if ( className.equals( JDT_IDE_PE_CLASS ) ) {
+            // the processing environment for the IDE integrated APT is in a different bundle than the APT classes
+            return "Eclipse JDT (IDE) " + getLibraryName( processingEnv.getTypeUtils().getClass(), true );
+        }
+
+        if ( className.equals( JDT_BATCH_PE_CLASS ) ) {
+            return "Eclipse JDT (Batch) " + getLibraryName( processingEnv.getClass(), true );
+        }
+
+        return processingEnv.getClass().getSimpleName() + " from " + getLibraryName( processingEnv.getClass(), false );
+    }
+
+    private static String getLibraryName(Class<?> clazz, boolean preferVersionOnly) {
+        String classFileName = asClassFileName( clazz.getName() );
+        URL resource = clazz.getClassLoader().getResource( classFileName );
+
+        Manifest manifest = openManifest( classFileName, resource );
+        if ( preferVersionOnly && manifest != null ) {
+            String version = manifest.getMainAttributes().getValue( "Bundle-Version" );
+
+            if ( version != null ) {
+                return version;
+            }
+        }
+
+        if ( "jar".equals( resource.getProtocol() ) ) {
+            return extractJarFileName( resource.getFile() );
+        }
+        else if ( "jrt".equals( resource.getProtocol() ) ) {
+            return extractJrtModuleName( resource );
+        }
+        else if ( "bundleresource".equals( resource.getProtocol() ) && manifest != null ) {
+            return extractBundleName( manifest );
+        }
+
+        return resource.toExternalForm();
+    }
+
+    private static Manifest openManifest(String classFileName, URL resource) {
+        try {
+            URL manifestUrl = createManifestUrl( classFileName, resource );
+            return new Manifest( manifestUrl.openStream() );
+        }
+        catch ( IOException e ) {
+            return null;
+        }
+    }
+
+    private static String extractBundleName(Manifest manifest) {
+        String version = manifest.getMainAttributes().getValue( "Bundle-Version" );
+        String symbolicName = manifest.getMainAttributes().getValue( "Bundle-SymbolicName" );
+        int semicolon = symbolicName.indexOf( ';' );
+        if ( semicolon > 0 ) {
+            symbolicName = symbolicName.substring( 0, semicolon );
+        }
+
+        return symbolicName + "_" + version;
+    }
+
+    private static String extractJrtModuleName(URL resource) {
+        // JDK 9 style, e.g. jrt:/jdk.compiler/com/sun/tools/javac/processing/JavacProcessingEnvironment.class
+        int moduleNameSeparator = resource.getFile().indexOf( '/', 1 );
+        if ( moduleNameSeparator > 1 ) {
+            return resource.getFile().substring( 1, moduleNameSeparator );
+        }
+        return resource.toExternalForm();
+    }
+
+    private static URL createManifestUrl(String classFileName, URL resource) throws MalformedURLException {
+        String classUrlString = resource.toExternalForm();
+        String baseFileUrl = classUrlString.substring( 0, classUrlString.length() - classFileName.length() );
+        return new URL( baseFileUrl + "META-INF/MANIFEST.MF" );
+    }
+
+    private static String asClassFileName(String className) {
+        return className.replace( '.', '/' ) + ".class";
+    }
+
+    private static String extractJarFileName(String file) {
+        int excl = file.indexOf( '!' );
+
+        if ( excl > 0 ) {
+            String fullFileName = file.substring( 0, excl );
+            // it's an URL, so it's not the system path separator char:
+            int lastPathSep = fullFileName.lastIndexOf( '/' );
+            if ( lastPathSep > 0 && lastPathSep < fullFileName.length() ) {
+                return fullFileName.substring( lastPathSep + 1 );
+            }
+        }
+
+        return file;
+    }
+
+    private static String initMapStructVersion() {
+        String classFileName = asClassFileName( DefaultVersionInformation.class.getName() );
+        URL resource = DefaultVersionInformation.class.getClassLoader().getResource( classFileName );
+        Manifest manifest = openManifest( classFileName, resource );
+
+        if ( null != manifest ) {
+            String version = manifest.getMainAttributes().getValue( "Implementation-Version" );
+            if ( version != null ) {
+                return version;
+            }
+        }
+        return "";
+    }
+}

processor/src/main/java/org/mapstruct/ap/processor/MapperCreationProcessor.java

@@ -23,6 +23,7 @@ import java.util.LinkedList;
 import java.util.List;
 import java.util.SortedSet;
 import java.util.TreeSet;
+
 import javax.annotation.processing.Messager;
 import javax.lang.model.element.ExecutableElement;
 import javax.lang.model.element.TypeElement;
@@ -56,6 +57,7 @@ import org.mapstruct.ap.prism.MapperPrism;
 import org.mapstruct.ap.processor.creation.MappingResolverImpl;
 import org.mapstruct.ap.util.MapperConfig;
 import org.mapstruct.ap.util.Strings;
+import org.mapstruct.ap.version.VersionInformation;
 
 /**
  * A {@link ModelElementProcessor} which creates a {@link Mapper} from the given
@@ -69,6 +71,7 @@ public class MapperCreationProcessor implements ModelElementProcessor<List<Sourc
     private Types typeUtils;
     private Messager messager;
     private Options options;
+    private VersionInformation versionInformation;
     private TypeFactory typeFactory;
     private MappingBuilderContext mappingContext;
 
@@ -78,6 +81,7 @@ public class MapperCreationProcessor implements ModelElementProcessor<List<Sourc
         this.typeUtils = context.getTypeUtils();
         this.messager = context.getMessager();
         this.options = context.getOptions();
+        this.versionInformation = context.getVersionInformation();
         this.typeFactory = context.getTypeFactory();
 
         List<MapperReference> mapperReferences = initReferencedMappers( mapperTypeElement );
@@ -140,7 +144,8 @@ public class MapperCreationProcessor implements ModelElementProcessor<List<Sourc
             .element( element )
             .mappingMethods( mappingMethods )
             .mapperReferences( mapperReferences )
-            .suppressGeneratorTimestamp( options.isSuppressGeneratorTimestamp() )
+            .options( options )
+            .versionInformation( versionInformation )
             .decorator( getDecorator( element, methods ) )
             .typeFactory( typeFactory )
             .elementUtils( elementUtils )
@@ -221,7 +226,8 @@ public class MapperCreationProcessor implements ModelElementProcessor<List<Sourc
             decoratorPrism,
             mappingMethods,
             hasDelegateConstructor,
-            options.isSuppressGeneratorTimestamp()
+            options,
+            versionInformation
         );
     }
 

processor/src/main/java/org/mapstruct/ap/processor/ModelElementProcessor.java

@@ -27,6 +27,7 @@ import javax.tools.Diagnostic.Kind;
 
 import org.mapstruct.ap.model.common.TypeFactory;
 import org.mapstruct.ap.option.Options;
+import org.mapstruct.ap.version.VersionInformation;
 
 /**
  * A processor which performs one task of the mapper generation, e.g. retrieving
@@ -62,6 +63,8 @@ public interface ModelElementProcessor<P, R> {
 
         Options getOptions();
 
+        VersionInformation getVersionInformation();
+
         /**
          * Whether the currently processed mapper type is erroneous which is the
          * case if at least one diagnostic with {@link Kind#ERROR} is reported

processor/src/main/java/org/mapstruct/ap/version/VersionInformation.java

@@ -0,0 +1,31 @@
+/**
+ *  Copyright 2012-2015 Gunnar Morling (http://www.gunnarmorling.de/)
+ *  and/or other contributors as indicated by the @authors tag. See the
+ *  copyright.txt file in the distribution for a full listing of all
+ *  contributors.
+ *
+ *  Licensed 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.
+ */
+package org.mapstruct.ap.version;
+
+/**
+ * Provides information about the processor version and the processor context implementation version
+ *
+ * @author Andreas Gudian
+ */
+public interface VersionInformation {
+    String getRuntimeVersion();
+    String getRuntimeVendor();
+    String getMapStructVersion();
+    String getCompiler();
+}

processor/src/main/java/org/mapstruct/ap/version/package-info.java

@@ -0,0 +1,24 @@
+/**
+ *  Copyright 2012-2015 Gunnar Morling (http://www.gunnarmorling.de/)
+ *  and/or other contributors as indicated by the @authors tag. See the
+ *  copyright.txt file in the distribution for a full listing of all
+ *  contributors.
+ *
+ *  Licensed 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.
+ */
+/**
+ * <p>
+ * Provides various version information
+ * </p>
+ */
+package org.mapstruct.ap.version;

processor/src/main/resources/org.mapstruct.ap.model.GeneratedType.ftl

@@ -26,8 +26,8 @@ import ${importedType.importName};
 
 @Generated(
     value = "org.mapstruct.ap.MappingProcessor"<#if suppressGeneratorTimestamp == false>,
-    date = "${.now?string("yyyy-MM-dd'T'HH:mm:ssZ")}"</#if><#if comments??>,
+    date = "${.now?string("yyyy-MM-dd'T'HH:mm:ssZ")}"</#if><#if suppressGeneratorVersionComment == false>,
-    comments = "${comments}"</#if>
+    comments = "version: ${versionInformation.mapStructVersion}, compiler: ${versionInformation.compiler}, environment: Java ${versionInformation.runtimeVersion} (${versionInformation.runtimeVendor})"</#if>
 )
 <#list annotations as annotation>
 <#nt><@includeModel object=annotation/>

processor/src/test/java/org/mapstruct/ap/test/versioninfo/SimpleMapper.java

@@ -0,0 +1,30 @@
+/**
+ *  Copyright 2012-2015 Gunnar Morling (http://www.gunnarmorling.de/)
+ *  and/or other contributors as indicated by the @authors tag. See the
+ *  copyright.txt file in the distribution for a full listing of all
+ *  contributors.
+ *
+ *  Licensed 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.
+ */
+package org.mapstruct.ap.test.versioninfo;
+
+import org.mapstruct.Mapper;
+
+/**
+ * @author Andreas Gudian
+ *
+ */
+@Mapper
+public interface SimpleMapper {
+    Object toObject(Object object);
+}

processor/src/test/java/org/mapstruct/ap/test/versioninfo/VersionInfoTest.java

@@ -0,0 +1,72 @@
+/**
+ *  Copyright 2012-2015 Gunnar Morling (http://www.gunnarmorling.de/)
+ *  and/or other contributors as indicated by the @authors tag. See the
+ *  copyright.txt file in the distribution for a full listing of all
+ *  contributors.
+ *
+ *  Licensed 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.
+ */
+package org.mapstruct.ap.test.versioninfo;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mapstruct.ap.testutil.IssueKey;
+import org.mapstruct.ap.testutil.WithClasses;
+import org.mapstruct.ap.testutil.compilation.annotation.ProcessorOption;
+import org.mapstruct.ap.testutil.compilation.annotation.ProcessorOptions;
+import org.mapstruct.ap.testutil.runner.AnnotationProcessorTestRunner;
+import org.mapstruct.ap.testutil.runner.GeneratedSource;
+
+/**
+ * @author Andreas Gudian
+ *
+ */
+@RunWith( AnnotationProcessorTestRunner.class )
+@IssueKey( "424" )
+@WithClasses( SimpleMapper.class )
+public class VersionInfoTest {
+    private final GeneratedSource generatedSource = new GeneratedSource();
+
+    @Rule
+    public GeneratedSource getGeneratedSource() {
+        return generatedSource;
+    }
+
+    @Test
+    @ProcessorOption( name = "mapstruct.suppressGeneratorVersionInfoComment", value = "true" )
+    public void includesNoComment() {
+        generatedSource.forMapper( SimpleMapper.class ).content()
+            .contains( "date = \"" )
+            .doesNotContain( "comments = \"version: " );
+    }
+
+    @Test
+    @ProcessorOptions( {
+        @ProcessorOption( name = "mapstruct.suppressGeneratorVersionInfoComment", value = "true" ),
+        @ProcessorOption( name = "mapstruct.suppressGeneratorTimestamp", value = "true" )
+    } )
+    public void includesNoCommentAndNoTimestamp() {
+        generatedSource.forMapper( SimpleMapper.class ).content()
+            .doesNotContain( "date = \"" )
+            .doesNotContain( "comments = \"version: " );
+    }
+
+    @Test
+    public void includesCommentAndTimestamp() {
+        generatedSource.forMapper( SimpleMapper.class ).content()
+            .contains( "date = \"" )
+            .contains( "comments = \"version: " );
+    }
+
+}