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 java.util.Collection;
020import java.util.Map;
021import java.util.Set;
022
023/**
024 * Provides a base decorator that enables additional functionality to be added
025 * to a Map via decoration.
026 * <p>
027 * Methods are forwarded directly to the decorated map.
028 * <p>
029 * This implementation does not perform any special processing with
030 * {@link #entrySet()}, {@link #keySet()} or {@link #values()}. Instead
031 * it simply returns the set/collection from the wrapped map. This may be
032 * undesirable, for example if you are trying to write a validating
033 * implementation it would provide a loophole around the validation.
034 * But, you might want that loophole, so this class is kept simple.
035 *
036 * @param <K> the type of the keys in the map
037 * @param <V> the type of the values in the map
038 * @since 3.0
039 * @version $Id: AbstractMapDecorator.html 972421 2015-11-14 20:00:04Z tn $
040 */
041public abstract class AbstractMapDecorator<K, V> extends AbstractIterableMap<K, V> {
042
043    /** The map to decorate */
044    transient Map<K, V> map;
045
046    /**
047     * Constructor only used in deserialization, do not use otherwise.
048     * @since 3.1
049     */
050    protected AbstractMapDecorator() {
051        super();
052    }
053
054    /**
055     * Constructor that wraps (not copies).
056     *
057     * @param map  the map to decorate, must not be null
058     * @throws IllegalArgumentException if the collection is null
059     */
060    protected AbstractMapDecorator(final Map<K, V> map) {
061        if (map == null) {
062            throw new IllegalArgumentException("Map must not be null");
063        }
064        this.map = map;
065    }
066
067    /**
068     * Gets the map being decorated.
069     *
070     * @return the decorated map
071     */
072    protected Map<K, V> decorated() {
073        return map;
074    }
075
076    //-----------------------------------------------------------------------
077    public void clear() {
078        decorated().clear();
079    }
080
081    public boolean containsKey(final Object key) {
082        return decorated().containsKey(key);
083    }
084
085    public boolean containsValue(final Object value) {
086        return decorated().containsValue(value);
087    }
088
089    public Set<Map.Entry<K, V>> entrySet() {
090        return decorated().entrySet();
091    }
092
093    public V get(final Object key) {
094        return decorated().get(key);
095    }
096
097    public boolean isEmpty() {
098        return decorated().isEmpty();
099    }
100
101    public Set<K> keySet() {
102        return decorated().keySet();
103    }
104
105    public V put(final K key, final V value) {
106        return decorated().put(key, value);
107    }
108
109    public void putAll(final Map<? extends K, ? extends V> mapToCopy) {
110        decorated().putAll(mapToCopy);
111    }
112
113    public V remove(final Object key) {
114        return decorated().remove(key);
115    }
116
117    public int size() {
118        return decorated().size();
119    }
120
121    public Collection<V> values() {
122        return decorated().values();
123    }
124
125    @Override
126    public boolean equals(final Object object) {
127        if (object == this) {
128            return true;
129        }
130        return decorated().equals(object);
131    }
132
133    @Override
134    public int hashCode() {
135        return decorated().hashCode();
136    }
137
138    @Override
139    public String toString() {
140        return decorated().toString();
141    }
142
143}