final String valueForFieldOnSupertype = "valueForFieldOnSupertype";
final String valueForFieldOnSelf = "valueForFieldOnSelf";
SimpleDtoSubTypeImpl dto = SimpleDtoSubTypeImpl.make();
dto.setName(valueForFieldOnSupertype);
dto.setAnotherField(valueForFieldOnSelf);
String json = dto.toJson();
assertTrue(json.contains(valueForFieldOnSelf));
assertTrue(json.contains(valueForFieldOnSupertype));
}