1 /*
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13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
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24  */
25 
26 
27 package sun.security.util;
28 
29 import java.util.Comparator;
30 
31 /**
32  * Compare two byte arrays in lexicographical order.
33  *
34  * @author D. N. Hoover
35  */
36 public class ByteArrayLexOrder implements Comparator<byte[]> {
37 
38     /**
39      * Perform lexicographical comparison of two byte arrays,
40      * regarding each byte as unsigned.  That is, compare array entries
41      * in order until they differ--the array with the smaller entry
42      * is "smaller". If array entries are
43      * equal till one array ends, then the longer array is "bigger".
44      *
45      * @param  bytes1 first byte array to compare.
46      * @param  bytes2 second byte array to compare.
47      * @return negative number if bytes1 < bytes2, 0 if bytes1 == bytes2,
48      * positive number if bytes1 > bytes2.
49      *
50      * @exception <code>ClassCastException</code>
51      * if either argument is not a byte array.
52      */
compare( byte[] bytes1, byte[] bytes2)53     public final int compare( byte[] bytes1, byte[] bytes2) {
54         int diff;
55         for (int i = 0; i < bytes1.length && i < bytes2.length; i++) {
56             diff = (bytes1[i] & 0xFF) - (bytes2[i] & 0xFF);
57             if (diff != 0) {
58                 return diff;
59             }
60         }
61         // if array entries are equal till the first ends, then the
62         // longer is "bigger"
63         return bytes1.length - bytes2.length;
64     }
65 
66 
67 }
68