Java tutorial
//package com.java2s; /* * Copyright (c) 2013 Game Salutes. * All rights reserved. This program and the accompanying materials * are made available under the terms of the GNU Lesser Public License v3 * which accompanies this distribution, and is available at * http://www.gnu.org/licenses/lgpl.html * * Contributors: * Game Salutes - Repackaging and modifications of original work under University of Chicago and Apache License 2.0 shown below * * Repackaging from edu.uchicago.nsit.iteco.utils to com.gamesalutes.utils * * Copyright 2008 - 2011 University of Chicago * * Licensed 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. ******************************************************************************/ import java.util.*; public class Main { /** * Returns a hashcode that is computed irrespective of the order of the collection. This method should be used * to compute a hashcode of a collection field when <code>unorderedListEquals</code> or * <code>unorderedCollectionEquals</code> is used for that field in the object's equals method. * * @param c the <code>Collection</code> * @return the hashcode */ public static int unorderedCollectionHashCode(Collection<?> c) { if (c == null) return 0; int h = 0; Iterator<?> i = c.iterator(); while (i.hasNext()) { Object o = i.next(); if (o != null) h += o.hashCode(); } return h; } }