001/*
002 *  Licensed to the Apache Software Foundation (ASF) under one
003 *  or more contributor license agreements.  See the NOTICE file
004 *  distributed with this work for additional information
005 *  regarding copyright ownership.  The ASF licenses this file
006 *  to you under the Apache License, Version 2.0 (the
007 *  "License"); you may not use this file except in compliance
008 *  with the License.  You may obtain a copy of the License at
009 *
010 *        http://www.apache.org/licenses/LICENSE-2.0
011 *
012 *  Unless required by applicable law or agreed to in writing,
013 *  software distributed under the License is distributed on an
014 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 *  KIND, either express or implied.  See the License for the
016 *  specific language governing permissions and limitations
017 *  under the License.
018 */
019
020package org.apache.isis.core.metamodel.facetdecorator;
021
022import org.apache.isis.core.metamodel.facetapi.Facet;
023import org.apache.isis.core.metamodel.facetapi.FacetHolder;
024
025public interface FacetDecorator {
026
027    /**
028     * If applicable, replace the provided {@link Facet} with a decorating
029     * {@link Facet} that should be held by the provided {@link FacetHolder
030     * required holder}.
031     * 
032     * <p>
033     * 
034     * @return the decorating {@link Facet}, or <tt>null</tt> if this decoration
035     *         does not apply to this Facet.
036     */
037    Facet decorate(Facet facet, FacetHolder requiredHolder);
038
039    Class<? extends Facet>[] getFacetTypes();
040
041    String getFacetTypeNames();
042
043}