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1   /*
2   	StatCvs - CVS statistics generation 
3   	Copyright (C) 2002  Lukasz Pekacki <lukasz@pekacki.de>
4   	http://statcvs.sf.net/
5       
6   	This library is free software; you can redistribute it and/or
7   	modify it under the terms of the GNU Lesser General Public
8   	License as published by the Free Software Foundation; either
9   	version 2.1 of the License, or (at your option) any later version.
10  
11  	This library is distributed in the hope that it will be useful,
12  	but WITHOUT ANY WARRANTY; without even the implied warranty of
13  	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  	Lesser General Public License for more details.
15  
16  	You should have received a copy of the GNU Lesser General Public
17  	License along with this library; if not, write to the Free Software
18  	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19      
20  	$RCSfile: FilePatternMatcher.java,v $
21  	$Date: 2008/04/02 11:22:15 $
22  */
23  package net.sf.statcvs.util;
24  
25  import java.util.ArrayList;
26  import java.util.Iterator;
27  import java.util.List;
28  import java.util.StringTokenizer;
29  import java.util.regex.Pattern;
30  
31  /**
32   * <p>Matches filenames against an Ant-style wildcard pattern list.</p>
33   * 
34   * <p>In short, ? matches one character, * matches zero or more characters
35   * but no directory changes (it doesn't match / or \), and **
36   * matches zero or more directory levels. If the wildcard pattern
37   * ends in / or \, an implicit ** is added.</p>
38   * 
39   * <p>Several patterns can be specified, seperated by : or ;.</p>
40   * 
41   * <p>Everything is case sensitive. If you need case insensitive pattern
42   * matching, use <tt>String.toLower()</tt> on the pattern and on the
43   * candidate string.</p>
44   *
45   * @author Richard Cyganiak <rcyg@gmx.de>
46   * @version $Id: FilePatternMatcher.java,v 1.3 2008/04/02 11:22:15 benoitx Exp $
47   */
48  public class FilePatternMatcher {
49      private final String originalPattern;
50      private final List patterns = new ArrayList();
51  
52      /**
53       * Creates a matcher to match filenames against a specified
54       * wildcard pattern
55       * @param wildcardPattern an Ant-style wildcard pattern
56       */
57      public FilePatternMatcher(final String wildcardPattern) {
58          this.originalPattern = wildcardPattern;
59          final StringTokenizer tokenizer = new StringTokenizer(wildcardPattern, ":;");
60          while (tokenizer.hasMoreTokens()) {
61              patterns.add(Pattern.compile(buildRegex(tokenizer.nextToken())));
62          }
63      }
64  
65      /**
66       * Matches a filename against the wildcard pattern.
67       * @param filename a filename
68       * @return <tt>true</tt> if the filename matches the pattern
69       */
70      public boolean matches(final String filename) {
71          final Iterator it = patterns.iterator();
72          while (it.hasNext()) {
73              final Pattern regex = (Pattern) it.next();
74              if (regex.matcher(filename).matches()) {
75                  return true;
76              }
77          }
78          return false;
79      }
80  
81      private String buildRegex(final String wildcardPattern) {
82          String temp = wildcardPattern;
83          temp = temp.replace('\\', '/');
84          if (temp.endsWith("/")) {
85              temp += "**";
86          }
87          // replace **/** with **
88          temp = temp.replaceAll("\\*\\*/\\*\\*", "**");
89          if ("**".equals(temp)) {
90              return ".*";
91          }
92          // replace **/ at start with (.*/)? and /** at end with (/.*)?
93          if (temp.startsWith("**/") && temp.endsWith("/**")) {
94              final String inner = temp.substring(3, temp.length() - 3);
95              return "(.*/)?" + buildInnerRegex(inner) + "(/.*)?";
96          }
97          if (temp.startsWith("**/")) {
98              final String inner = temp.substring(3);
99              return "(.*/)?" + buildInnerRegex(inner);
100         }
101         if (temp.endsWith("/**")) {
102             final String inner = temp.substring(0, temp.length() - 3);
103             return buildInnerRegex(inner) + "(/.*)?";
104         }
105         return buildInnerRegex(temp);
106     }
107 
108     private String buildInnerRegex(final String wildcardPattern) {
109         // replace /**/ with /(.*/)?
110         final int pos = wildcardPattern.indexOf("/**/");
111         if (pos > -1) {
112             final String before = wildcardPattern.substring(0, pos);
113             final String after = wildcardPattern.substring(pos + 4);
114             return buildInnerRegex(before) + "/(.*/)?" + buildInnerRegex(after);
115         }
116         // replace ? with [^/] and * with [^/]*
117         return wildcardPattern.replaceAll("\\?", "[^/]").replaceAll("\\*", "[^/]*");
118     }
119 
120     public String toString() {
121         return this.originalPattern;
122     }
123 }