1 package org.codehaus.mojo.taglist.tags;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import java.util.regex.Matcher;
23 import java.util.regex.Pattern;
24 import java.util.Locale;
25
26 /** The regular expression tag class.
27 *
28 * This class defines a regular express tag search. This tag
29 * will match if the regular express string listed is found within
30 * the scanned lines.
31 *
32 * Example POM:
33 * <pre>
34 * <project>
35 * ...
36 * <matchString>fixme[0-9]</matchString>
37 * <matchType>regEx</matchType>
38 * ...
39 * </project>
40 * </pre>
41 *
42 * Example Java code with match:
43 * <pre>
44 * fixme1 this will match (fixme followed by one digit.)
45 * </pre>
46 *
47 * Example Java code without match:
48 * <pre>
49 * fixme this will NOT match (no digit after fixme)
50 * </pre>
51 *
52 */
53 public class RegExTag extends AbsTag
54 {
55 /** The regular expression pattern to pre-compile. */
56 private Pattern pattern = null;
57
58 /** The length of the last regEx comment tag match */
59 private int lastMatchedCommentTagLength = 0;
60
61 /** Check to see if the string contains this tag.
62 * If there is a match, return the index within the string; otherwise,
63 * return NO_MATCH.
64 *
65 * @param currentLine the string for the current line being scanned.
66 * @param locale the Locale of the currentLine.
67 * @return the index within the string of the matched tag, or TagClass.NO_MATCH
68 * if not match was found.
69 */
70 public int contains( final String currentLine, final Locale locale )
71 {
72 int result = AbsTag.NO_MATCH;
73
74 if ( currentLine != null )
75 {
76 // Get index match or -1 if no match
77 Matcher m = pattern.matcher( currentLine );
78 if ( m.find() )
79 {
80 result = m.start();
81
82 // Store the length of the comment tag.
83 lastMatchedCommentTagLength = m.end() - m.start();
84 }
85 }
86
87 return ( result );
88 }
89
90 /** Check to see if the string starts with this tag.
91 *
92 * @param currentLine the string for the current line being scanned.
93 * @param locale the Locale of the currentLine.
94 * @return true if the string starts with this tag.
95 */
96 public boolean startsWith( final String currentLine, final Locale locale )
97 {
98 boolean result = false;
99
100 if ( currentLine != null )
101 {
102 Matcher m = pattern.matcher( currentLine );
103 if ( m.find() )
104 {
105 // Was the match at the first character?
106 result = m.start() == 0;
107 }
108 }
109
110 return ( result );
111 }
112
113 /** Return the length of the last matched tag.
114 *
115 * A regular expression tag might be 10 characters; however,
116 * the matched string may only be 5.
117 *
118 * Example:
119 * regEx tag: a*b (tag length = 3)
120 *
121 * matched comment: aaabbb (comment length = 6)
122 *
123 * In the above example, this function will return 6.
124 *
125 * @return the length of the last matched tag.
126 */
127 public int getLastTagMatchLength()
128 {
129 return ( lastMatchedCommentTagLength );
130 }
131
132 /** Constructor.
133 *
134 * @param tagString the string to match against for this tag.
135 */
136 public RegExTag ( final String tagString )
137 {
138 super( tagString );
139
140 // Pre-compile the regular expression
141 pattern = Pattern.compile( tagString );
142
143 }
144
145 }