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 * https://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.i18n.I18n;
24 import org.apache.directory.api.ldap.model.schema.LdapComparator;
25 import org.apache.directory.api.util.Strings;
26 import org.slf4j.Logger;
27 import org.slf4j.LoggerFactory;
28
29
30 /**
31 * <p>
32 * A comparator for Words/KeyWords. RFC 4517 par. 4.2.21 (KeywordMatch) and par.
33 * 4.2.32 is pretty vague about the definition of what is a word or a keyword
34 * ("...The precise definition of a word is implementation specific...)
35 * ("...The identification of keywords in the attribute value and the exactness
36 * of the match are both implementation specific...).
37 * <p>
38 * We will simply check that the assertion is present in the value at some place,
39 * after having deep trimmed the word.
40 * <p>
41 * For instance, the word " World " will be found in the value "Hello world!".
42 * <p>
43 * A word is defined by the following regexp : "(^|[^A-Za-z0-9])([A-Za-z0-9])*([^A-Za-z0-9]|$)".
44 * Anything that is not matched by this regexp will not be considered as a word.
45 *
46 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
47 */
48 public class WordComparator extends LdapComparator<String>
49 {
50 /** The serial version UID */
51 private static final long serialVersionUID = 2L;
52
53 /** A logger for this class */
54 private static final Logger LOG = LoggerFactory.getLogger( WordComparator.class );
55
56
57 /**
58 * The StringComparator constructor. Its OID is the StringMatch matching
59 * rule OID.
60 *
61 * @param oid The Comparator's OID
62 */
63 public WordComparator( String oid )
64 {
65 super( oid );
66 }
67
68
69 /**
70 * {@inheritDoc}
71 */
72 public int compare( String value, String assertion )
73 {
74 if ( LOG.isDebugEnabled() )
75 {
76 LOG.debug( I18n.msg( I18n.MSG_13749_COMPARING_STRING, value, assertion ) );
77 }
78
79 if ( value == assertion )
80 {
81 return 0;
82 }
83
84 // -------------------------------------------------------------------
85 // Handle some basis cases
86 // -------------------------------------------------------------------
87 if ( ( value == null ) || ( assertion == null ) )
88 {
89 return ( assertion == null ) ? 1 : -1;
90 }
91
92 // Now, trim the assertion and find it in the value
93 String trimmedAssertion = Strings.trim( assertion );
94 int pos = value.indexOf( trimmedAssertion );
95
96 if ( pos != -1 )
97 {
98 int assertionLength = trimmedAssertion.length();
99
100 // Check that we are not in a middle of some text
101 if ( assertionLength == value.length() )
102 {
103 return 0;
104 }
105
106 if ( pos == 0 )
107 {
108 char after = value.charAt( assertionLength );
109
110 if ( !Character.isLetterOrDigit( after ) )
111 {
112 return 0;
113 }
114 else
115 {
116 return -1;
117 }
118 }
119
120 if ( pos + assertionLength == value.length() )
121 {
122 char before = value.charAt( value.length() - assertionLength - 1 );
123
124 if ( !Character.isLetterOrDigit( before ) )
125 {
126 return 0;
127 }
128 else
129 {
130 return -1;
131 }
132 }
133
134 char before = value.charAt( value.length() - assertionLength );
135 char after = value.charAt( assertionLength );
136
137 if ( Character.isLetterOrDigit( after ) )
138 {
139 return -1;
140 }
141
142 if ( !Character.isLetterOrDigit( before ) )
143 {
144 return -1;
145 }
146
147 return 0;
148 }
149
150 return -1;
151 }
152 }