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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.vfs.provider.jar;
18  
19  import org.apache.commons.vfs.FileName;
20  import org.apache.commons.vfs.FileSystemException;
21  import org.apache.commons.vfs.provider.zip.ZipFileObject;
22  
23  import java.io.IOException;
24  import java.security.cert.Certificate;
25  import java.util.HashMap;
26  import java.util.Iterator;
27  import java.util.Map;
28  import java.util.jar.Attributes;
29  import java.util.jar.JarEntry;
30  import java.util.jar.JarFile;
31  import java.util.jar.Manifest;
32  import java.util.zip.ZipEntry;
33  
34  /***
35   * A file in a Jar file system.
36   *
37   * @author <a href="mailto:brian@mmmanager.org">Brian Olsen</a>
38   * @version $Revision: 480428 $ $Date: 2006-11-29 07:15:24 +0100 (Mi, 29 Nov 2006) $
39   */
40  public class JarFileObject extends ZipFileObject
41  {
42      private Attributes attributes;
43  
44      final JarFileSystem fs;
45  
46      protected JarFileObject(final FileName name,
47                              final ZipEntry entry,
48                              final JarFileSystem fs,
49                              final boolean zipExists) throws FileSystemException
50      {
51          super(name, entry, fs, zipExists);
52          this.fs = fs;
53  
54          try
55          {
56              getAttributes(); // early get the attributes as the zip file might be closed
57          }
58          catch (IOException e)
59          {
60              throw new FileSystemException(e);
61          }
62      }
63  
64      /***
65       * Returns the Jar manifest.
66       */
67      Manifest getManifest() throws IOException
68      {
69          if (fs.getZipFile() == null)
70          {
71              return null;
72          }
73  
74          return ((JarFile) fs.getZipFile()).getManifest();
75      }
76  
77      /***
78       * Returns the attributes of this file.
79       */
80      Attributes getAttributes() throws IOException
81      {
82          if (attributes == null)
83          {
84              if (entry == null)
85              {
86                  attributes = new Attributes(1);
87              }
88              else
89              {
90                  attributes = ((JarEntry) entry).getAttributes();
91                  if (attributes == null)
92                  {
93                      attributes = new Attributes(1);
94                  }
95              }
96          }
97  
98          return attributes;
99      }
100 
101     /***
102      * Returns the value of an attribute.
103      */
104     protected Map doGetAttributes()
105         throws Exception
106     {
107         final Map attrs = new HashMap();
108 
109         // Add the file system's attributes first
110         final JarFileSystem fs = (JarFileSystem) getFileSystem();
111         addAll(fs.getAttributes(), attrs);
112 
113         // Add this file's attributes
114         addAll(getAttributes(), attrs);
115 
116         return attrs;
117     }
118 
119     /***
120      * Adds the source attributes to the destination map.
121      */
122     private void addAll(final Attributes src, final Map dest)
123     {
124         for (Iterator iterator = src.entrySet().iterator(); iterator.hasNext();)
125         {
126             final Map.Entry entry = (Map.Entry) iterator.next();
127             final String name = entry.getKey().toString().toLowerCase();
128             dest.put(name, entry.getValue());
129         }
130     }
131 
132     /***
133      * Return the certificates of this JarEntry.
134      */
135     protected Certificate[] doGetCertificates()
136     {
137         if (entry == null)
138         {
139             return null;
140         }
141 
142         return ((JarEntry) entry).getCertificates();
143     }
144 }