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 */ 017package org.apache.commons.collections4.map; 018 019import org.apache.commons.collections4.OrderedMap; 020import org.apache.commons.collections4.OrderedMapIterator; 021 022/** 023 * Provides a base decorator that enables additional functionality to be added 024 * to an OrderedMap via decoration. 025 * <p> 026 * Methods are forwarded directly to the decorated map. 027 * <p> 028 * This implementation does not perform any special processing with the map views. 029 * Instead it simply returns the set/collection from the wrapped map. This may be 030 * undesirable, for example if you are trying to write a validating implementation 031 * it would provide a loophole around the validation. 032 * But, you might want that loophole, so this class is kept simple. 033 * 034 * @param <K> the type of the keys in this map 035 * @param <V> the type of the values in this map 036 * @since 3.0 037 */ 038public abstract class AbstractOrderedMapDecorator<K, V> extends AbstractMapDecorator<K, V> 039 implements OrderedMap<K, V> { 040 041 /** 042 * Constructor only used in deserialization, do not use otherwise. 043 * @since 3.1 044 */ 045 protected AbstractOrderedMapDecorator() { 046 super(); 047 } 048 049 /** 050 * Constructor that wraps (not copies). 051 * 052 * @param map the map to decorate, must not be null 053 * @throws NullPointerException if the map is null 054 */ 055 public AbstractOrderedMapDecorator(final OrderedMap<K, V> map) { 056 super(map); 057 } 058 059 /** 060 * Gets the map being decorated. 061 * 062 * @return the decorated map 063 */ 064 @Override 065 protected OrderedMap<K, V> decorated() { 066 return (OrderedMap<K, V>) super.decorated(); 067 } 068 069 //----------------------------------------------------------------------- 070 @Override 071 public K firstKey() { 072 return decorated().firstKey(); 073 } 074 075 @Override 076 public K lastKey() { 077 return decorated().lastKey(); 078 } 079 080 @Override 081 public K nextKey(final K key) { 082 return decorated().nextKey(key); 083 } 084 085 @Override 086 public K previousKey(final K key) { 087 return decorated().previousKey(key); 088 } 089 090 @Override 091 public OrderedMapIterator<K, V> mapIterator() { 092 return decorated().mapIterator(); 093 } 094 095}