Source for gnu.java.net.loader.JarURLResource

   1: /* JarURLResource.java -- a Resource for jar URLs
   2:    Copyright (C) 2006 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package gnu.java.net.loader;
  40: 
  41: 
  42: import java.io.IOException;
  43: import java.io.InputStream;
  44: import java.net.MalformedURLException;
  45: import java.net.URL;
  46: import java.security.cert.Certificate;
  47: import java.util.jar.JarEntry;
  48: 
  49: public final class JarURLResource extends Resource
  50: {
  51:   private final JarEntry entry;
  52:   private final String name;
  53: 
  54:   public JarURLResource(JarURLLoader loader, String name, JarEntry entry)
  55:   {
  56:     super(loader);
  57:     this.entry = entry;
  58:     this.name = name;
  59:   }
  60: 
  61:   public InputStream getInputStream() throws IOException
  62:   {
  63:     return ((JarURLLoader) loader).jarfile.getInputStream(entry);
  64:   }
  65: 
  66:   public int getLength()
  67:   {
  68:     return (int) entry.getSize();
  69:   }
  70: 
  71:   public Certificate[] getCertificates()
  72:   {
  73:     // We have to get the entry from the jar file again, because the
  74:     // certificates will not be available until the entire entry has
  75:     // been read.
  76:     return ((JarEntry) ((JarURLLoader) loader).jarfile.getEntry(name))
  77:       .getCertificates();
  78:   }
  79: 
  80:   public URL getURL()
  81:   {
  82:     try
  83:       {
  84:         return new URL(((JarURLLoader) loader).baseJarURL, name,
  85:                        loader.cache.get(loader.factory, "jar"));
  86:       }
  87:     catch (MalformedURLException e)
  88:       {
  89:         InternalError ie = new InternalError();
  90:         ie.initCause(e);
  91:         throw ie;
  92:       }
  93:   }
  94: }