001    /*
002     *  Licensed to the Apache Software Foundation (ASF) under one or more
003     *  contributor license agreements.  See the NOTICE file distributed with
004     *  this work for additional information regarding copyright ownership.
005     *  The ASF licenses this file to You under the Apache License, Version 2.0
006     *  (the "License"); you may not use this file except in compliance with
007     *  the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     *  Unless required by applicable law or agreed to in writing, software
012     *  distributed under the License is distributed on an "AS IS" BASIS,
013     *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     *  See the License for the specific language governing permissions and
015     *  limitations under the License.
016     */
017    package org.apache.commons.collections;
018    
019    import java.util.Map;
020    
021    /**
022     * Defines a map that can be iterated directly without needing to create an entry set.
023     * <p>
024     * A map iterator is an efficient way of iterating over maps.
025     * There is no need to access the entry set or cast to Map Entry objects.
026     * <pre>
027     * IterableMap map = new HashedMap();
028     * MapIterator it = map.mapIterator();
029     * while (it.hasNext()) {
030     *   Object key = it.next();
031     *   Object value = it.getValue();
032     *   it.setValue("newValue");
033     * }
034     * </pre>
035     * 
036     * @since Commons Collections 3.0
037     * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
038     *
039     * @author Stephen Colebourne
040     */
041    public interface IterableMap extends Map {
042    
043        /**
044         * Obtains a <code>MapIterator</code> over the map.
045         * <p>
046         * A map iterator is an efficient way of iterating over maps.
047         * There is no need to access the entry set or cast to Map Entry objects.
048         * <pre>
049         * IterableMap map = new HashedMap();
050         * MapIterator it = map.mapIterator();
051         * while (it.hasNext()) {
052         *   Object key = it.next();
053         *   Object value = it.getValue();
054         *   it.setValue("newValue");
055         * }
056         * </pre>
057         * 
058         * @return a map iterator
059         */
060        MapIterator mapIterator();
061        
062    }