Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.commons.collections.iterators; import java.util.Iterator; import org.apache.commons.collections.ResettableIterator; /** * Provides an implementation of an empty iterator. * <p> * This class provides an implementation of an empty iterator. * This class provides for binary compatability between Commons Collections * 2.1.1 and 3.1 due to issues with <code>IteratorUtils</code>. * * @since Commons Collections 2.1.1 and 3.1 * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $ * * @author Stephen Colebourne */ public class EmptyIterator extends AbstractEmptyIterator implements ResettableIterator { /** * Singleton instance of the iterator. * @since Commons Collections 3.1 */ public static final ResettableIterator RESETTABLE_INSTANCE = new EmptyIterator(); /** * Singleton instance of the iterator. * @since Commons Collections 2.1.1 and 3.1 */ public static final Iterator INSTANCE = RESETTABLE_INSTANCE; /** * Constructor. */ protected EmptyIterator() { super(); } }