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