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1   /*
2    * Copyright (c) 2003-2004, Henri Yandell
3    * All rights reserved.
4    * 
5    * Redistribution and use in source and binary forms, with or 
6    * without modification, are permitted provided that the 
7    * following conditions are met:
8    * 
9    * + Redistributions of source code must retain the above copyright notice, 
10   *   this list of conditions and the following disclaimer.
11   * 
12   * + Redistributions in binary form must reproduce the above copyright notice, 
13   *   this list of conditions and the following disclaimer in the documentation 
14   *   and/or other materials provided with the distribution.
15   * 
16   * + Neither the name of Genjava-Core nor the names of its contributors 
17   *   may be used to endorse or promote products derived from this software 
18   *   without specific prior written permission.
19   * 
20   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
21   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
22   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
23   * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
24   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
25   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
26   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
27   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
28   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
29   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
30   * POSSIBILITY OF SUCH DAMAGE.
31   */
32  package com.generationjava.util;
33  
34  import java.util.ArrayList;
35  
36  /***
37   * An implementation of Wildcard logic, as seen on command lines 
38   * on UNIX and DOS.
39   */
40  public class WildcardUtils {
41  
42      /***
43       * See if a particular piece of text, often a filename, 
44       * matches to a specified wildcard. 
45       */
46      public static boolean match(String text, String wildcard) {
47          // split wildcard on ? and *
48          // for each element of the array, find a matching block in text
49          // earliest matching block counts
50          String[] wcs = splitOnTokens(wildcard);
51          int textIdx = 0;
52          for(int i=0; i<wcs.length; i++) {
53              if(textIdx == text.length()) {
54                  if("*".equals(wcs[i])) {
55                      return true;
56                  }
57                  return wcs[i].length() == 0;
58              }
59  
60              if("?".equals(wcs[i])) {
61                  textIdx++;
62              } else
63              if("*".equals(wcs[i])) {
64                  int nextIdx = i+1;
65                  if(nextIdx == wcs.length) {
66                      return true;
67                  }
68                  int restartIdx = text.indexOf(wcs[nextIdx], textIdx);
69                  if(restartIdx == -1) {
70                      return false;
71                  } else {
72                      textIdx = restartIdx;
73                  }
74              } else {
75                  if(!text.startsWith(wcs[i], textIdx)) {
76                      return false;
77                  } else {
78                      textIdx += wcs[i].length();
79                  }
80              }
81          }
82  
83          return true;
84      }
85  
86      // package level so a unit test may run on this
87      static String[] splitOnTokens(String text) {
88          char[] array = text.toCharArray();
89          if(text.indexOf("?") == -1 && text.indexOf("*") == -1) {
90              return new String[] { text };
91          }
92  
93          ArrayList list = new ArrayList();
94          StringBuffer buffer = new StringBuffer();
95          for(int i=0; i<array.length; i++) {
96              if(array[i] == '?' || array[i] == '*') {
97                  if(buffer.length() != 0) {
98                     list.add(buffer.toString());
99                     buffer.setLength(0);
100                 }
101                 list.add(new String( new char[] { array[i] } ));
102             } else {
103                 buffer.append(array[i]);
104             }
105         }
106         if(buffer.length() != 0) {
107             list.add(buffer.toString());
108         }
109 
110         return (String[]) list.toArray(new String[0]);
111     }
112         
113 
114 }