Package org.mapstruct

Annotation Type SubclassMapping

@Repeatable(SubclassMappings.class)
@Retention(CLASS)
@Target({METHOD,ANNOTATION_TYPE})
@Experimental
public @interface SubclassMapping

Configures the mapping to handle hierarchy of the source type.

The subclass to be mapped is to be specified via source(). The subclass to map to is to be specified via target().

This annotation can be combined with @Mapping annotations.

 @Mapper
 public interface MyMapper {
    @SubclassMapping (target = TargetSubclass.class, source = SourceSubclass.class)
    TargetParent mapParent(SourceParent parent);

    TargetSubclass mapSubclass(SourceSubclass subInstant);
 }
 

Below follow examples of the implementation for the mapParent method. Example 1: For parents that cannot be created. (e.g. abstract classes or interfaces)

 // generates
 @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());
     }
 }
 

Example 2: For parents that can be created. (e.g. normal classes or interfaces with @Mappper( uses = ObjectFactory.class ) )

 // generates
 @Override
 public TargetParent mapParent(SourceParent parent) {
     TargetParent targetParent1;
     if (parent instanceof SourceSubclass) {
         targetParent1 = mapSubclass( (SourceSubclass) parent );
     }
     else {
         targetParent1 = new TargetParent();
         // ...
     }
 }
 

Since:

1.5

Author:

Ben Zegveld

Required Element Summary

Required Elements

Modifier and Type	Required Element	Description
Class<?>	source
Class<?>	target

Element Detail

source

Class<?> source

Returns:

the source subclass to check for before using the default mapping as fallback.

target

Class<?> target

Returns:

the target subclass to map the source to.