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.SortedMap; 020 021 /** 022 * Defines a map that allows bidirectional lookup between key and values 023 * and retains both keys and values in sorted order. 024 * <p> 025 * Implementations should allow a value to be looked up from a key and 026 * a key to be looked up from a value with equal performance. 027 * 028 * @since Commons Collections 3.0 029 * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $ 030 * 031 * @author Stephen Colebourne 032 */ 033 public interface SortedBidiMap extends OrderedBidiMap, SortedMap { 034 035 /** 036 * Gets a view of this map where the keys and values are reversed. 037 * <p> 038 * Changes to one map will be visible in the other and vice versa. 039 * This enables both directions of the map to be accessed equally. 040 * <p> 041 * Implementations should seek to avoid creating a new object every time this 042 * method is called. See <code>AbstractMap.values()</code> etc. Calling this 043 * method on the inverse map should return the original. 044 * <p> 045 * Implementations must return a <code>SortedBidiMap</code> instance, 046 * usually by forwarding to <code>inverseSortedBidiMap()</code>. 047 * 048 * @return an inverted bidirectional map 049 */ 050 public BidiMap inverseBidiMap(); 051 052 /** 053 * Gets a view of this map where the keys and values are reversed. 054 * <p> 055 * Changes to one map will be visible in the other and vice versa. 056 * This enables both directions of the map to be accessed as a <code>SortedMap</code>. 057 * <p> 058 * Implementations should seek to avoid creating a new object every time this 059 * method is called. See <code>AbstractMap.values()</code> etc. Calling this 060 * method on the inverse map should return the original. 061 * <p> 062 * The inverse map returned by <code>inverseBidiMap()</code> should be the 063 * same object as returned by this method. 064 * 065 * @return an inverted bidirectional map 066 */ 067 public SortedBidiMap inverseSortedBidiMap(); 068 069 }