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1   /*
2    * $HeadURL: https://svn.apache.org/repos/asf/httpcomponents/oac.hc3x/trunk/src/java/org/apache/commons/httpclient/util/LangUtils.java $
3    * $Revision$
4    * $Date$
5    *
6    * ====================================================================
7    *
8    *  Licensed to the Apache Software Foundation (ASF) under one or more
9    *  contributor license agreements.  See the NOTICE file distributed with
10   *  this work for additional information regarding copyright ownership.
11   *  The ASF licenses this file to You under the Apache License, Version 2.0
12   *  (the "License"); you may not use this file except in compliance with
13   *  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, software
18   *  distributed under the License is distributed on an "AS IS" BASIS,
19   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
20   *  See the License for the specific language governing permissions and
21   *  limitations under the License.
22   * ====================================================================
23   *
24   * This software consists of voluntary contributions made by many
25   * individuals on behalf of the Apache Software Foundation.  For more
26   * information on the Apache Software Foundation, please see
27   * <http://www.apache.org/>.
28   *
29   */
30  
31  package org.apache.commons.httpclient.util;
32  
33  /***
34   * A set of utility methods to help produce consistent Object#equals(Object) and
35   * Object#hashCode methods.
36   *  
37   * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
38   * 
39   * @since 3.0
40   */
41  public class LangUtils {
42      
43      public static final int HASH_SEED = 17;
44      public static final int HASH_OFFSET = 37;
45      
46      private LangUtils() {
47          super();
48      }
49  
50      public static int hashCode(final int seed, final int hashcode) {
51          return seed * HASH_OFFSET + hashcode;
52      }
53  
54      public static int hashCode(final int seed, final Object obj) {
55          return hashCode(seed, obj != null ? obj.hashCode() : 0);
56      }
57      
58      public static int hashCode(final int seed, final boolean b) {
59          return hashCode(seed, b ? 1 : 0);
60      }
61      
62      public static boolean equals(final Object obj1, final Object obj2) {
63          return obj1 == null ? obj2 == null : obj1.equals(obj2);
64      }
65  
66  }