1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.directory.api.ldap.model.schema.comparators;
21
22
23 import org.apache.directory.api.ldap.model.schema.LdapComparator;
24 import org.apache.directory.api.util.Strings;
25 import org.slf4j.Logger;
26 import org.slf4j.LoggerFactory;
27
28
29 /**
30 * A comparator for byte[]s.
31 *
32 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
33 */
34 public class ByteArrayComparator extends LdapComparator<byte[]>
35 {
36 /** The serial version UID */
37 private static final long serialVersionUID = 2L;
38
39 /** A logger for this class */
40 private static final Logger LOG = LoggerFactory.getLogger( ByteArrayComparator.class );
41
42
43 /**
44 * The ByteArrayComparator constructor. Its OID is the OctetStringMatch matching
45 * rule OID.
46 */
47 public ByteArrayComparator( String oid )
48 {
49 super( oid );
50 }
51
52
53 /**
54 * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object)
55 */
56 public int compare( byte[] b1, byte[] b2 )
57 {
58 LOG.debug( "comparing OctetString objects '{}' with '{}'",
59 Strings.dumpBytes( b1 ), Strings.dumpBytes( b2 ) );
60
61 // -------------------------------------------------------------------
62 // Handle some basis cases
63 // -------------------------------------------------------------------
64
65 if ( b1 == null )
66 {
67 return ( b2 == null ) ? 0 : -1;
68 }
69
70 if ( b2 == null )
71 {
72 return 1;
73 }
74
75 if ( b1.length == b2.length )
76 {
77 for ( int i = 0; i < b1.length; i++ )
78 {
79 if ( b1[i] > b2[i] )
80 {
81 return 1;
82 }
83 else if ( b1[i] < b2[i] )
84 {
85 return -1;
86 }
87 }
88
89 return 0;
90 }
91
92 int minLength = Math.min( b1.length, b2.length );
93
94 for ( int i = 0; i < minLength; i++ )
95 {
96 if ( b1[i] > b2[i] )
97 {
98 return 1;
99 }
100 else if ( b1[i] < b2[i] )
101 {
102 return -1;
103 }
104 }
105
106 // b2 is longer w/ b1 as prefix
107 if ( b1.length == minLength )
108 {
109 return -1;
110 }
111
112 // b1 is longer w/ b2 as prefix
113 if ( b2.length == minLength )
114 {
115 return 1;
116 }
117
118 return 0;
119 }
120 }