Query/View/Transformation Operational Mapping Language - Eclipse Modeling Project: A Domain-Specific Language Toolkit - page 561

mapping dnc::Archetype::toSerializableClass() : java::JavaClass
inherits dnc::Archetype::toClass {
implementsInterfaces += 'java.io.Serializable'. map toClass();

}

mapping dnc::Archetype::toStateful() : java::JavaClass
inherits dnc::Archetype::toSerializableClass {

eAnnotations += toAnnotation('description', self .description, null );
eAnnotations += toAnnotation('annotation', '@Stateful', null );
classImport += 'javax.ejb.Stateful'. map toClass();

}

In this example, toStateful() inherits from toSerializableClass() ,
which, in turn, inherits from toClass() .

merges
Sometimes a mapping operation produces multiple outputs or results in an object
that is the logical combination of other defined mappings. By allowing for the
merging of mapping operations, the language of the transformation more closely
approximates a natural language. In terms of execution semantics, the merged
mappings are invoked following the end of the merging mapping. All mappings,
including out , are passed to the merged mapping.
We can modify our previous inherits example to include merges for the
serializable aspect of the stateful class. In this case, a stateful bean is a class that
also is serializable.

mapping dnc::Archetype::toClass() : java::JavaClass {
name := self .name;
fields += self .getAttributes(). map toField( result );
methods += self .getOperations(). map toMethod();

}

mapping dnc::Archetype::toSerializableClass() : java::JavaClass {
implementsInterfaces += 'java.io.Serializable'. map toClass();

}

mapping dnc::Archetype::toStateful() : java::JavaClass
inherits dnc::Archetype::toClass
merges dnc::Archetype::toSerializableClass {

eAnnotations += toAnnotation('description', self .description, null );
eAnnotations += toAnnotation('annotation', '@Stateful', null );
classImport += 'javax.ejb.Stateful'. map toClass();

}