    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 *      https://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.keyvalue;
    018
    019import java.util.Map;
    020import java.util.Map.Entry;
    021import java.util.Objects;
    022
    023import org.apache.commons.collections4.KeyValue;
    024
    025/**
    026 * Provides a base decorator that allows additional functionality to be
    027 * added to a {@link Entry Map.Entry}.
    028 *
    029 * @param <K> The type of keys
    030 * @param <V> The type of mapped values
    031 * @since 3.0
    032 */
    033public abstract class AbstractMapEntryDecorator<K, V> implements Map.Entry<K, V>, KeyValue<K, V> {
    034
    035    /** The {@code Map.Entry} to decorate */
    036    private final Map.Entry<K, V> entry;
    037
    038    /**
    039     * Constructor that wraps (not copies).
    040     *
    041     * @param entry  The {@code Map.Entry} to decorate, must not be null
    042     * @throws NullPointerException if the collection is null
    043     */
    044    public AbstractMapEntryDecorator(final Map.Entry<K, V> entry) {
    045        this.entry = Objects.requireNonNull(entry, "entry");
    046    }
    047
    048    @Override
    049    public boolean equals(final Object object) {
    050        if (object == this) {
    051            return true;
    052        }
    053        return entry.equals(object);
    054    }
    055
    056    @Override
    057    public K getKey() {
    058        return entry.getKey();
    059    }
    060
    061    /**
    062     * Gets the map being decorated.
    063     *
    064     * @return The decorated map
    065     */
    066    protected Map.Entry<K, V> getMapEntry() {
    067        return entry;
    068    }
    069
    070    @Override
    071    public V getValue() {
    072        return entry.getValue();
    073    }
    074
    075    @Override
    076    public int hashCode() {
    077        return entry.hashCode();
    078    }
    079
    080    @Override
    081    public V setValue(final V value) {
    082        return entry.setValue(value);
    083    }
    084
    085    @Override
    086    public String toString() {
    087        return entry.toString();
    088    }
    089
    090}