#1449 Adders should not be considered as builder setter methods

processor/src/main/java/org/mapstruct/ap/spi/DefaultAccessorNamingStrategy.java

@@ -102,6 +102,7 @@ public class DefaultAccessorNamingStrategy implements AccessorNamingStrategy {
     protected boolean isBuilderSetter(ExecutableElement method) {
         return method.getParameters().size() == 1 &&
             !JAVA_JAVAX_PACKAGE.matcher( method.getEnclosingElement().asType().toString() ).matches() &&
+            !isAdderMethod( method ) &&
             //TODO The Types need to be compared with Types#isSameType(TypeMirror, TypeMirror)
             method.getReturnType().toString().equals( method.getEnclosingElement().asType().toString() );
     }

processor/src/test/java/org/mapstruct/ap/test/builder/simple/SimpleBuilderMapper.java

@@ -18,11 +18,12 @@
  */
 package org.mapstruct.ap.test.builder.simple;
 
+import org.mapstruct.CollectionMappingStrategy;
 import org.mapstruct.Mapper;
 import org.mapstruct.Mapping;
 import org.mapstruct.Mappings;
 
-@Mapper
+@Mapper(collectionMappingStrategy = CollectionMappingStrategy.ADDER_PREFERRED)
 public interface SimpleBuilderMapper {
 
     @Mappings({

processor/src/test/java/org/mapstruct/ap/test/builder/simple/SimpleImmutableBuilderTest.java

@@ -18,6 +18,8 @@
  */
 package org.mapstruct.ap.test.builder.simple;
 
+import java.util.Arrays;
+
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -48,6 +50,7 @@ public class SimpleImmutableBuilderTest {
         SimpleMutablePerson source = new SimpleMutablePerson();
         source.setAge( 3 );
         source.setFullName( "Bob" );
+        source.setChildren( Arrays.asList( "Alice", "Tom" ) );
 
         SimpleImmutablePerson targetObject = mapper.toImmutable( source );
 
@@ -55,6 +58,7 @@ public class SimpleImmutableBuilderTest {
         assertThat( targetObject.getName() ).isEqualTo( "Bob" );
         assertThat( targetObject.getJob() ).isEqualTo( "programmer" );
         assertThat( targetObject.getCity() ).isEqualTo( "Bengalore" );
+        assertThat( targetObject.getChildren() ).contains( "Alice", "Tom" );
     }
 
     @Test

processor/src/test/java/org/mapstruct/ap/test/builder/simple/SimpleImmutablePerson.java

@@ -18,17 +18,22 @@
  */
 package org.mapstruct.ap.test.builder.simple;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class SimpleImmutablePerson {
     private final String name;
     private final int age;
     private final String job;
     private final String city;
+    private final List<String> children;
 
     SimpleImmutablePerson(Builder builder) {
         this.name = builder.name;
         this.age = builder.age;
         this.job = builder.job;
         this.city = builder.city;
+        this.children = new ArrayList<String>( builder.children );
     }
 
     public static Builder builder() {
@@ -51,11 +56,16 @@ public class SimpleImmutablePerson {
         return city;
     }
 
+    public List<String> getChildren() {
+        return children;
+    }
+
     public static class Builder {
         private String name;
         private int age;
         private String job;
         private String city;
+        private List<String> children = new ArrayList<String>();
 
         public Builder age(int age) {
             this.age = age;
@@ -80,5 +90,14 @@ public class SimpleImmutablePerson {
             this.city = city;
             return this;
         }
+
+        public List<String> getChildren() {
+            throw new UnsupportedOperationException( "This is just a marker method" );
+        }
+
+        public Builder addChild(String child) {
+            this.children.add( child );
+            return this;
+        }
     }
 }

processor/src/test/java/org/mapstruct/ap/test/builder/simple/SimpleMutablePerson.java

@@ -18,9 +18,12 @@
  */
 package org.mapstruct.ap.test.builder.simple;
 
+import java.util.List;
+
 public class SimpleMutablePerson {
     private String fullName;
     private int age;
+    private List<String> children;
 
     public int getAge() {
         return age;
@@ -37,4 +40,12 @@ public class SimpleMutablePerson {
     public void setFullName(String fullName) {
         this.fullName = fullName;
     }
+
+    public List<String> getChildren() {
+        return children;
+    }
+
+    public void setChildren(List<String> children) {
+        this.children = children;
+    }
 }