### Question:
TypeDraftBuilder extends TypeDraftBuilderBase<TypeDraftBuilder> { public static TypeDraftBuilder of(final String key, final LocalizedString name, final ResourceTypeIdsSetBuilder resourceTypeIdsSetBuilder) { return of(key, name, resourceTypeIdsSetBuilder.build()); } TypeDraftBuilder(@Nullable final LocalizedString description, @Nullable final List<FieldDefinition> fieldDefinitions, final String key, final LocalizedString name, final Set<String> resourceTypeIds); static TypeDraftBuilder of(final String key, final LocalizedString name, final ResourceTypeIdsSetBuilder resourceTypeIdsSetBuilder);  }### Answer:
@Test public void plusFieldDefinitionsTests() { final LocalizedString l = LocalizedString.of(Locale.GERMAN, "l"); final TypeDraftBuilder builder = TypeDraftBuilder.of("type-key", l, ResourceTypeIdsSetBuilder.of().addCategories()); builder.plusFieldDefinitions( FieldDefinition.of( ReferenceFieldType.of(Category.referenceTypeId()), "fieldName", l, false) ).build(); }