/*
* Copyright 2003-2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.collections;
/**
* Defines a map that allows bidirectional lookup between key and values
* and retains and provides access to an ordering.
* <p>
* Implementations should allow a value to be looked up from a key and
* a key to be looked up from a value with equal performance.
*
* @since Commons Collections 3.0
* @version $Revision: 155406 $ $Date: 2005-02-26 12:55:26 +0000 (Sat, 26 Feb 2005) $
*
* @author Stephen Colebourne
*/
public interface OrderedBidiMap extends BidiMap, OrderedMap {
/**
* Gets a view of this map where the keys and values are reversed.
* <p>
* Changes to one map will be visible in the other and vice versa.
* This enables both directions of the map to be accessed equally.
* <p>
* Implementations should seek to avoid creating a new object every time this
* method is called. See <code>AbstractMap.values()</code> etc. Calling this
* method on the inverse map should return the original.
* <p>
* Implementations must return an <code>OrderedBidiMap</code> instance,
* usually by forwarding to <code>inverseOrderedBidiMap()</code>.
*
* @return an inverted bidirectional map
*/
public BidiMap inverseBidiMap();
/**
* Gets a view of this map where the keys and values are reversed.
* <p>
* Changes to one map will be visible in the other and vice versa.
* This enables both directions of the map to be accessed equally.
* <p>
* Implementations should seek to avoid creating a new object every time this
* method is called. See <code>AbstractMap.values()</code> etc. Calling this
* method on the inverse map should return the original.
*
* @return an inverted bidirectional map
*/
public OrderedBidiMap inverseOrderedBidiMap();
}