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