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.iterators;
018
019import org.apache.commons.collections4.MapIterator;
020
021/**
022 * Provides basic behaviour for decorating a map iterator with extra functionality.
023 * <p>
024 * All methods are forwarded to the decorated map iterator.
025 *
026 * @param <K> the type of keys
027 * @param <V> the type of mapped values
028 * @since 3.0
029 */
030public class AbstractMapIteratorDecorator<K, V> implements MapIterator<K, V> {
031
032    /** The iterator being decorated */
033    private final MapIterator<K, V> iterator;
034
035    //-----------------------------------------------------------------------
036    /**
037     * Constructor that decorates the specified iterator.
038     *
039     * @param iterator  the iterator to decorate, must not be null
040     * @throws NullPointerException if the iterator is null
041     */
042    public AbstractMapIteratorDecorator(final MapIterator<K, V> iterator) {
043        super();
044        if (iterator == null) {
045            throw new NullPointerException("MapIterator must not be null");
046        }
047        this.iterator = iterator;
048    }
049
050    /**
051     * Gets the iterator being decorated.
052     *
053     * @return the decorated iterator
054     */
055    protected MapIterator<K, V> getMapIterator() {
056        return iterator;
057    }
058
059    //-----------------------------------------------------------------------
060
061    /** {@inheritDoc} */
062    @Override
063    public boolean hasNext() {
064        return iterator.hasNext();
065    }
066
067    /** {@inheritDoc} */
068    @Override
069    public K next() {
070        return iterator.next();
071    }
072
073    /** {@inheritDoc} */
074    @Override
075    public void remove() {
076        iterator.remove();
077    }
078
079    /** {@inheritDoc} */
080    @Override
081    public K getKey() {
082        return iterator.getKey();
083    }
084
085    /** {@inheritDoc} */
086    @Override
087    public V getValue() {
088        return iterator.getValue();
089    }
090
091    /** {@inheritDoc} */
092    @Override
093    public V setValue(final V obj) {
094        return iterator.setValue(obj);
095    }
096
097}