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Types that extend and augment the Java Collections Framework.
/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2003-2004 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowledgement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact [email protected].
*
* 5. Products derived from this software may not be called "Apache"
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* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* SortedMap to create objects in the map on demand.
*
* When the {@link #get(Object)} method is called with a key that does not
* exist in the map, the factory is used to create the object. The created
* object will be added to the map using the requested key.
*
* For instance:
*
* Factory factory = new Factory() {
* public Object create() {
* return new Date();
* }
* }
* SortedMap lazy = Lazy.sortedMap(new HashMap(), factory);
* Object obj = lazy.get("NOW");
*
*
* After the above code is executed, obj will contain
* a new Date instance. Furthermore, that Date
* instance is mapped to the "NOW" key in the map.
*
* @since Commons Collections 3.0
* @version $Revision: 1.3 $ $Date: 2004/01/14 21:43:11 $
*
* @author Stephen Colebourne
* @author Paul Jack
*/
public class LazySortedMap
extends LazyMap implements SortedMap {
/**
* Factory method to create a lazily instantiated sorted map.
*
* @param map the map to decorate, must not be null
* @param factory the factory to use, must not be null
* @throws IllegalArgumentException if map or factory is null
*/
public static SortedMap decorate(SortedMap map, Factory factory) {
return new LazySortedMap(map, factory);
}
/**
* Factory method to create a lazily instantiated sorted map.
*
* @param map the map to decorate, must not be null
* @param factory the factory to use, must not be null
* @throws IllegalArgumentException if map or factory is null
*/
public static SortedMap decorate(SortedMap map, Transformer factory) {
return new LazySortedMap(map, factory);
}
//-----------------------------------------------------------------------
/**
* Constructor that wraps (not copies).
*
* @param map the map to decorate, must not be null
* @param factory the factory to use, must not be null
* @throws IllegalArgumentException if map or factory is null
*/
protected LazySortedMap(SortedMap map, Factory factory) {
super(map, factory);
}
/**
* Constructor that wraps (not copies).
*
* @param map the map to decorate, must not be null
* @param factory the factory to use, must not be null
* @throws IllegalArgumentException if map or factory is null
*/
protected LazySortedMap(SortedMap map, Transformer factory) {
super(map, factory);
}
/**
* Gets the map being decorated.
*
* @return the decorated map
*/
protected SortedMap getSortedMap() {
return (SortedMap) map;
}
//-----------------------------------------------------------------------
public Object firstKey() {
return getSortedMap().firstKey();
}
public Object lastKey() {
return getSortedMap().lastKey();
}
public Comparator comparator() {
return getSortedMap().comparator();
}
public SortedMap subMap(Object fromKey, Object toKey) {
SortedMap map = getSortedMap().subMap(fromKey, toKey);
return new LazySortedMap(map, factory);
}
public SortedMap headMap(Object toKey) {
SortedMap map = getSortedMap().headMap(toKey);
return new LazySortedMap(map, factory);
}
public SortedMap tailMap(Object fromKey) {
SortedMap map = getSortedMap().tailMap(fromKey);
return new LazySortedMap(map, factory);
}
}