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.OrderedIterator;
020import org.apache.commons.collections4.ResettableIterator;
021
022/**
023 * Provides an implementation of an empty ordered iterator.
024 *
025 * @param <E> the type of elements returned by this iterator.
026 * @since 3.1
027 */
028public class EmptyOrderedIterator<E> extends AbstractEmptyIterator<E>
029        implements OrderedIterator<E>, ResettableIterator<E> {
030
031    /**
032     * Singleton instance of the iterator.
033     * @since 3.1
034     */
035    @SuppressWarnings("rawtypes")
036    public static final OrderedIterator INSTANCE = new EmptyOrderedIterator<>();
037
038    /**
039     * Typed instance of the iterator.
040     * @param <E> the element type
041     * @return OrderedIterator&lt;E&gt;
042     */
043    public static <E> OrderedIterator<E> emptyOrderedIterator() {
044        return INSTANCE;
045    }
046
047    /**
048     * Constructs a new instance.
049     */
050    protected EmptyOrderedIterator() {
051    }
052
053}