#82 Use Mappers factory to instanciate used mappers annotated with @Mapper

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

@@ -23,6 +23,7 @@ import java.util.Set;
 
 import org.mapstruct.ap.util.Collections;
 import org.mapstruct.ap.util.Strings;
+import org.mapstruct.ap.util.TypeFactory;
 
 /**
  * Mapper reference which is retrieved via the {@code Mappers#getMapper()} method. Used by default if no other component
@@ -33,9 +34,18 @@ import org.mapstruct.ap.util.Strings;
 public class DefaultMapperReference extends AbstractModelElement implements MapperReference {
 
     private final Type type;
+    private final boolean isAnnotatedMapper;
+    private final Set<Type> importTypes;
 
-    public DefaultMapperReference(Type type) {
+    public DefaultMapperReference(Type type, TypeFactory typeFactory) {
         this.type = type;
+
+        isAnnotatedMapper = type.isAnnotatedWith( "org.mapstruct.ap.model.Mapper" );
+        importTypes = Collections.asSet( type );
+
+        if ( isAnnotatedMapper() ) {
+            importTypes.add( typeFactory.getType( "org.mapstruct.factory.Mappers" ) );
+        }
     }
 
     @Override
@@ -45,10 +55,14 @@ public class DefaultMapperReference extends AbstractModelElement implements Mapp
 
     @Override
     public Set<Type> getImportTypes() {
-        return Collections.asSet( type );
+        return importTypes;
     }
 
     public String getVariableName() {
         return Strings.getSaveVariableName( Introspector.decapitalize( type.getName() ) );
     }
+
+    public boolean isAnnotatedMapper() {
+        return isAnnotatedMapper;
+    }
 }

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

@@ -21,7 +21,10 @@ package org.mapstruct.ap.model;
 import java.util.Collections;
 import java.util.List;
 import java.util.Set;
+
+import javax.lang.model.element.AnnotationMirror;
 import javax.lang.model.element.ElementKind;
+import javax.lang.model.element.Name;
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.type.DeclaredType;
 import javax.lang.model.type.TypeKind;
@@ -161,6 +164,23 @@ public class Type extends AbstractModelElement implements Comparable<Type> {
             Collections.<Type>emptySet();
     }
 
+    /**
+     * @param annotationTypeName the fully qualified name of the annotation type
+     * @return true, if the type is annotated with an annotation of the specified type (super-types are not inspected)
+     */
+    public boolean isAnnotatedWith(String annotationTypeName) {
+        List<? extends AnnotationMirror> annotationMirrors = typeElement.getAnnotationMirrors();
+
+        for ( AnnotationMirror mirror : annotationMirrors ) {
+            Name mirrorAnnotationName = ( (TypeElement) mirror.getAnnotationType().asElement() ).getQualifiedName();
+            if ( mirrorAnnotationName.contentEquals( annotationTypeName ) ) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     /**
      * Whether this type is assignable to the given other type.
      *

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

@@ -147,7 +147,7 @@ public class MapperCreationProcessor implements ModelElementProcessor<List<Metho
         MapperPrism mapperPrism = MapperPrism.getInstanceOn( element );
 
         for ( TypeMirror usedMapper : mapperPrism.uses() ) {
-            mapperReferences.add( new DefaultMapperReference( typeFactory.getType( usedMapper ) ) );
+            mapperReferences.add( new DefaultMapperReference( typeFactory.getType( usedMapper ), typeFactory ) );
         }
 
         return mapperReferences;

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

@@ -18,4 +18,4 @@
      limitations under the License.
 
 -->
-private final ${mapperType.name} ${variableName} = new ${mapperType.name}();
+private final ${mapperType.name} ${variableName} = <#if annotatedMapper>Mappers.getMapper( ${mapperType.name}.class );<#else>new ${mapperType.name}();</#if>