1 /* 2 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/util/LangUtils.java $ 3 * $Revision: 503413 $ 4 * $Date: 2007-02-04 06:22:14 -0800 (Sun, 04 Feb 2007) $ 5 * 6 * ==================================================================== 7 * Licensed to the Apache Software Foundation (ASF) under one 8 * or more contributor license agreements. See the NOTICE file 9 * distributed with this work for additional information 10 * regarding copyright ownership. The ASF licenses this file 11 * to you under the Apache License, Version 2.0 (the 12 * "License"); you may not use this file except in compliance 13 * with the License. You may obtain a copy of the License at 14 * 15 * http://www.apache.org/licenses/LICENSE-2.0 16 * 17 * Unless required by applicable law or agreed to in writing, 18 * software distributed under the License is distributed on an 19 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 20 * KIND, either express or implied. See the License for the 21 * specific language governing permissions and limitations 22 * under the License. 23 * ==================================================================== 24 * 25 * This software consists of voluntary contributions made by many 26 * individuals on behalf of the Apache Software Foundation. For more 27 * information on the Apache Software Foundation, please see 28 * <http://www.apache.org/>. 29 * 30 */ 31 32 package org.apache.http.util; 33 34 /** 35 * A set of utility methods to help produce consistent 36 * {@link Object#equals equals} and {@link Object#hashCode hashCode} methods. 37 * 38 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a> 39 * 40 * @since 4.0 41 */ 42 public final class LangUtils { 43 44 public static final int HASH_SEED = 17; 45 public static final int HASH_OFFSET = 37; 46 47 /** Disabled default constructor. */ 48 private LangUtils() { 49 } 50 51 public static int hashCode(final int seed, final int hashcode) { 52 return seed * HASH_OFFSET + hashcode; 53 } 54 55 public static int hashCode(final int seed, final boolean b) { 56 return hashCode(seed, b ? 1 : 0); 57 } 58 59 public static int hashCode(final int seed, final Object obj) { 60 return hashCode(seed, obj != null ? obj.hashCode() : 0); 61 } 62 63 public static boolean equals(final Object obj1, final Object obj2) { 64 return obj1 == null ? obj2 == null : obj1.equals(obj2); 65 } 66 67 public static boolean equals(final Object[] a1, final Object[] a2) { 68 if (a1 == null) { 69 if (a2 == null) { 70 return true; 71 } else { 72 return false; 73 } 74 } else { 75 if (a2 != null && a1.length == a2.length) { 76 for (int i = 0; i < a1.length; i++) { 77 if (!equals(a1[i], a2[i])) { 78 return false; 79 } 80 } 81 return true; 82 } else { 83 return false; 84 } 85 } 86 } 87 88 } 89