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.Iterator;
020import java.util.Objects;
021
022/**
023 * Provides basic behavior for decorating an iterator with extra functionality without committing the generic type of the Iterator implementation.
024 * <p>
025 * All methods are forwarded to the decorated iterator.
026 * </p>
027 *
028 * @param <I> the type of the iterator being decorated.
029 * @param <O> the type of elements returned by this iterator.
030 *
031 * @since 4.0
032 */
033public abstract class AbstractUntypedIteratorDecorator<I, O> implements Iterator<O> {
034
035    /** The iterator being decorated */
036    private final Iterator<I> iterator;
037
038    /**
039     * Create a new AbstractUntypedIteratorDecorator.
040     *
041     * @param iterator  the iterator to decorate
042     * @throws NullPointerException if the iterator is null
043     */
044    protected AbstractUntypedIteratorDecorator(final Iterator<I> iterator) {
045        this.iterator = Objects.requireNonNull(iterator, "iterator");
046    }
047
048    /**
049     * Gets the iterator being decorated.
050     *
051     * @return the decorated iterator
052     */
053    protected Iterator<I> getIterator() {
054        return iterator;
055    }
056
057    @Override
058    public boolean hasNext() {
059        return iterator.hasNext();
060    }
061
062    @Override
063    public void remove() {
064        iterator.remove();
065    }
066
067}