// GenericsNote: Converted.
/*
* Copyright 2001-2004 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 php.runtime.common.collections;
/**
* Defines a map that maintains order and allows both forward and backward
* iteration through that order.
*
* @author Matt Hall, John Watkinson, Stephen Colebourne
* @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:19 $
* @since Commons Collections 3.0
*/
public interface OrderedMap <K,V> extends IterableMap<K, V> {
/**
* Obtains an <code>OrderedMapIterator</code> over the map.
* <p/>
* A ordered map iterator is an efficient way of iterating over maps
* in both directions.
* <pre>
* }
* </pre>
*
* @return a map iterator
*/
OrderedMapIterator<K, V> orderedMapIterator();
/**
* Gets the first key currently in this map.
*
* @return the first key currently in this map
* @throws java.util.NoSuchElementException
* if this map is empty
*/
public K firstKey();
/**
* Gets the last key currently in this map.
*
* @return the last key currently in this map
* @throws java.util.NoSuchElementException
* if this map is empty
*/
public K lastKey();
/**
* Gets the next key after the one specified.
*
* @param key the key to search for next from
* @return the next key, null if no match or at end
*/
public K nextKey(K key);
/**
* Gets the previous key before the one specified.
*
* @param key the key to search for previous from
* @return the previous key, null if no match or at start
*/
public K previousKey(K key);
}