View Javadoc

1   package org.codehaus.classworlds.uberjar.protocol.jar;
2   
3   /*
4    $Id: Handler.java,v 1.1.1.1 2004/07/01 13:59:19 jvanzyl Exp $
5   
6    Copyright 2002 (C) The Werken Company. All Rights Reserved.
7    
8    Redistribution and use of this software and associated documentation
9    ("Software"), with or without modification, are permitted provided
10   that the following conditions are met:
11  
12   1. Redistributions of source code must retain copyright
13      statements and notices.  Redistributions must also contain a
14      copy of this document.
15   
16   2. Redistributions in binary form must reproduce the
17      above copyright notice, this list of conditions and the
18      following disclaimer in the documentation and/or other
19      materials provided with the distribution.
20   
21   3. The name "classworlds" must not be used to endorse or promote
22      products derived from this Software without prior written
23      permission of The Werken Company.  For written permission,
24      please contact bob@werken.com.
25   
26   4. Products derived from this Software may not be called "classworlds"
27      nor may "classworlds" appear in their names without prior written
28      permission of The Werken Company. "classworlds" is a registered
29      trademark of The Werken Company.
30   
31   5. Due credit should be given to The Werken Company.
32      (http://classworlds.werken.com/).
33   
34   THIS SOFTWARE IS PROVIDED BY THE WERKEN COMPANY AND CONTRIBUTORS
35   ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
36   NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
37   FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
38   THE WERKEN COMPANY OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
39   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
40   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
41   SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
42   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
43   STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
44   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
45   OF THE POSSIBILITY OF SUCH DAMAGE.
46   
47   */
48  
49  import java.io.IOException;
50  import java.net.URL;
51  import java.net.URLConnection;
52  import java.net.URLStreamHandler;
53  
54  /***
55   * <code>URLStreamHandler</code> for <code>jar:</code> protocol <code>URL</code>s.
56   *
57   * @author <a href="mailto:bob@eng.werken.com">bob mcwhirter</a>
58   * @version $Id: Handler.java,v 1.1.1.1 2004/07/01 13:59:19 jvanzyl Exp $
59   */
60  public class Handler
61      extends URLStreamHandler
62  {
63      // ----------------------------------------------------------------------
64      //     Class members
65      // ----------------------------------------------------------------------
66  
67      /***
68       * Singleton instance.
69       */
70      private static final Handler INSTANCE = new Handler();
71  
72      // ----------------------------------------------------------------------
73      //     Class methods
74      // ----------------------------------------------------------------------
75  
76      /***
77       * Retrieve the singleton instance.
78       *
79       * @return The singleton instance.
80       */
81      public static Handler getInstance()
82      {
83          return INSTANCE;
84      }
85  
86      // ----------------------------------------------------------------------
87      //     Constructors
88      // ----------------------------------------------------------------------
89  
90  
91      /***
92       * Construct.
93       */
94      public Handler()
95      {
96          // intentionally left blank
97      }
98  
99      // ----------------------------------------------------------------------
100     //     Instance methods
101     // ----------------------------------------------------------------------
102 
103     /***
104      * @see java.net.URLStreamHandler
105      */
106     public URLConnection openConnection( URL url )
107         throws IOException
108     {
109         return new JarUrlConnection( url );
110     }
111 
112     /***
113      * @see java.net.URLStreamHandler
114      */
115     public void parseURL( URL url,
116                           String spec,
117                           int start,
118                           int limit )
119     {
120         String specPath = spec.substring( start,
121                                           limit );
122 
123         String urlPath = null;
124 
125         if ( specPath.charAt( 0 ) == '/' )
126         {
127             urlPath = specPath;
128         }
129         else if ( specPath.charAt( 0 ) == '!' )
130         {
131             String relPath = url.getFile();
132 
133             int bangLoc = relPath.lastIndexOf( "!" );
134 
135             if ( bangLoc < 0 )
136             {
137                 urlPath = relPath + specPath;
138             }
139             else
140             {
141                 urlPath = relPath.substring( 0,
142                                              bangLoc ) + specPath;
143             }
144         }
145         else
146         {
147             String relPath = url.getFile();
148 
149             if ( relPath != null )
150             {
151                 int lastSlashLoc = relPath.lastIndexOf( "/" );
152 
153                 if ( lastSlashLoc < 0 )
154                 {
155                     urlPath = "/" + specPath;
156                 }
157                 else
158                 {
159                     urlPath = relPath.substring( 0,
160                                                  lastSlashLoc + 1 ) + specPath;
161                 }
162             }
163             else
164             {
165                 urlPath = specPath;
166             }
167         }
168 
169         setURL( url,
170                 "jar",
171                 null,
172                 0,
173                 null,
174                 null,
175                 urlPath,
176                 null,
177                 null );
178     }
179 }