001    /*
002     *  Copyright 2003-2004 The Apache Software Foundation
003     *
004     *  Licensed under the Apache License, Version 2.0 (the "License");
005     *  you may not use this file except in compliance with the License.
006     *  You may obtain a copy of the License at
007     *
008     *      http://www.apache.org/licenses/LICENSE-2.0
009     *
010     *  Unless required by applicable law or agreed to in writing, software
011     *  distributed under the License is distributed on an "AS IS" BASIS,
012     *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     *  See the License for the specific language governing permissions and
014     *  limitations under the License.
015     */
016    package org.apache.commons.convert1.util;
017    
018    import java.util.HashMap;
019    import java.util.Iterator;
020    
021    /**
022     * A map which stores objects by a key Class.
023     * When obtaining the object, it will check inheritence and 
024     * interface trees to see if the Class matches.
025     */
026    public class ClassMap extends ProxyMap {
027    
028        private Inheritor inh;
029        
030        public ClassMap() {
031            this(new BasicInheritor());
032        }
033        
034        public ClassMap(Inheritor inh) {
035            super(new HashMap());
036            this.inh = inh;
037        }
038        
039        public Inheritor getInheritor() {
040            return inh;
041        }
042        
043        /**
044         * Get the object from the map. If the key is not 
045         * a Class object, then it uses the Class of the object.
046         */
047        public Object get(Object key) {
048            if(key == null) {
049                return null;
050            }
051            Class clss = null;
052    
053            if(key instanceof Class) {
054                clss = (Class) key;
055            } else {
056                clss = key.getClass();
057            }
058    
059            Object obj = super.get(clss);
060    
061            if(obj == null) {
062    
063                inh.setTarget(clss);
064                Iterator itr = inh.iterator();
065                while(itr.hasNext() && obj == null) {
066                    obj = super.get(itr.next());
067                }
068            }
069    
070            return obj;
071        }
072    
073    }