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1   /*
2    * Redistribution and use of this software and associated documentation
3    * ("Software"), with or without modification, are permitted provided
4    * that the following conditions are met:
5    *
6    * 1. Redistributions of source code must retain copyright
7    *    statements and notices.  Redistributions must also contain a
8    *    copy of this document.
9    *
10   * 2. Redistributions in binary form must reproduce the
11   *    above copyright notice, this list of conditions and the
12   *    following disclaimer in the documentation and/or other
13   *    materials provided with the distribution.
14   *
15   * 3. The name "Exolab" must not be used to endorse or promote
16   *    products derived from this Software without prior written
17   *    permission of Intalio, Inc.  For written permission,
18   *    please contact info@exolab.org.
19   *
20   * 4. Products derived from this Software may not be called "Exolab"
21   *    nor may "Exolab" appear in their names without prior written
22   *    permission of Intalio, Inc. Exolab is a registered
23   *    trademark of Intalio, Inc.
24   *
25   * 5. Due credit should be given to the Exolab Project
26   *    (http://www.exolab.org/).
27   *
28   * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS
29   * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
30   * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
31   * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
32   * INTALIO, INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
33   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
34   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
35   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
37   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
39   * OF THE POSSIBILITY OF SUCH DAMAGE.
40   *
41   * Copyright 1999 (C) Intalio, Inc. All Rights Reserved.
42   *
43   * $Id: CompareHelper.java 6785 2007-01-29 05:09:59Z ekuns $
44   */
45  package org.castor.xmlctf;
46  
47  import java.lang.reflect.Array;
48  
49  /**
50   * Assists in the comparison of objects.  This method is used by generated
51   * code but is not used within the CTF directly.
52   *
53   * @author <a href="mailto:gignoux@intalio.com">Sebastien Gignoux</a>
54   * @version $Revision: 6785 $ $Date: 2003-10-15 09:17:49 -0600 (Wed, 15 Oct 2003) $
55   */
56  public class CompareHelper {
57  
58      /**
59       * Compare two objects. Return true if they are both null or if they are
60       * equal. This comparison method has special handling for arrays: For
61       * arrays, each element is compared.
62       * <p>
63       * Warning: We will throw a NullPointerException if any element of either
64       * array is null.
65       *
66       * @param o1 first object
67       * @param o2 second object
68       * @return true if both objects are both null or otherwise are equal
69       */
70      public static boolean equals(Object o1, Object o2) {
71          if (o1 == null && o2 == null) {
72              return true;
73          }
74  
75          if ((o1 != null && o2 == null) || (o1 == null && o2 != null)) {
76              return false;
77          }
78  
79          // From now we can safely assume (o1 != null && o2 != null)
80  
81          if (! o1.getClass().equals(o2.getClass())) {
82              return false;
83          }
84  
85          if (o1.getClass().isArray()) {
86              return compareArray(o1, o2);
87          }
88  
89          return o1.equals(o2);
90      }
91  
92      /**
93       * Compares two arrays, returning true if the arrays contain the same
94       * values.
95       * <p>
96       * Warning: We will throw a NullPointerException if any element of either
97       * array is null.
98       *
99       * @param o1 The first array
100      * @param o2 The second array
101      * @return true if the two objects represent arrays with the same values
102      */
103     private static boolean compareArray(Object o1, Object o2) {
104         int size = Array.getLength(o1);
105 
106         if (size != Array.getLength(o2))
107             return false;
108 
109         Class component = o1.getClass().getComponentType();
110 
111         if ( ! component.equals(o2.getClass().getComponentType()))
112             return false;
113 
114         if (component.isPrimitive()) {
115             return comparePrimitiveArray(o1, o2);
116         }
117 
118         for (int i=0; i < size; ++i) {
119             if (! Array.get(o1, i).equals(Array.get(o2, i))) {
120                 return false;
121             }
122         }
123 
124         return true;
125     }
126 
127     /**
128      * Compares two arrays of primitive values. The caller should have tested
129      * that the two array have the same length and that the component type are
130      * equal.
131      *
132      * @param o1 The first array
133      * @param o2 The second array
134      * @return true if the two objects represent arrays of the same primitive
135      *         values
136      */
137     public static boolean comparePrimitiveArray(Object o1, Object o2) {
138         Class component = o1.getClass().getComponentType();
139         int size = Array.getLength(o1);
140 
141         if (component.equals(Boolean.TYPE)) {
142             for (int i=0; i<size; ++i) {
143                 if (Array.getBoolean(o1, i) != Array.getBoolean(o2, i)) {
144                     return false;
145                 }
146             }
147 
148             return true;
149         } else if (component.equals(Byte.TYPE)) {
150             for (int i=0; i<size; ++i) {
151                 if (Array.getByte(o1, i) != Array.getByte(o2, i)) {
152                     return false;
153                 }
154             }
155 
156             return true;
157         } else if (component.equals(Character.TYPE)) {
158             for (int i=0; i<size; ++i) {
159                 if (Array.getChar(o1, i) != Array.getChar(o2, i)) {
160                     return false;
161                 }
162             }
163 
164             return true;
165         } else if (component.equals(Double.TYPE)) {
166             for (int i=0; i<size; ++i) {
167                 if (Array.getDouble(o1, i) != Array.getDouble(o2, i)) {
168                     return false;
169                 }
170             }
171 
172             return true;
173         } else if (component.equals(Float.TYPE)) {
174             for (int i=0; i<size; ++i) {
175                 if (Array.getFloat(o1, i) != Array.getFloat(o2, i)) {
176                     return false;
177                 }
178             }
179 
180             return true;
181         } else if (component.equals(Integer.TYPE)) {
182             for (int i=0; i<size; ++i) {
183                 if (Array.getInt(o1, i) != Array.getInt(o2, i)) {
184                     return false;
185                 }
186             }
187 
188             return true;
189         } else if (component.equals(Long.TYPE)) {
190             for (int i=0; i<size; ++i) {
191                 if (Array.getLong(o1, i) != Array.getLong(o2, i)) {
192                     return false;
193                 }
194             }
195 
196             return true;
197         } else if (component.equals(Short.TYPE)) {
198             for (int i=0; i<size; ++i) {
199                 if (Array.getShort(o1, i) != Array.getShort(o2, i)) {
200                     return false;
201                 }
202             }
203 
204             return true;
205         } else {
206             throw new IllegalArgumentException("Unexpected primitive type " + component.toString());
207         }
208     }
209 
210 }