1 /*
   2  * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.net.www.protocol.jar;
  27 
  28 import java.io.IOException;
  29 import java.io.FileNotFoundException;
  30 import java.net.URL;
  31 import java.net.URLConnection;
  32 import java.util.HashMap;
  33 import java.util.jar.JarFile;
  34 import java.security.Permission;
  35 import sun.net.util.URLUtil;
  36 
  37 /* A factory for cached JAR file. This class is used to both retrieve
  38  * and cache Jar files.
  39  *
  40  * @author Benjamin Renaud
  41  * @since JDK1.2
  42  */
  43 class JarFileFactory implements URLJarFile.URLJarFileCloseController {
  44 
  45     /* the url to file cache */
  46     private static HashMap<String, JarFile> fileCache = new HashMap<String, JarFile>();
  47 
  48     /* the file to url cache */
  49     private static HashMap<JarFile, URL> urlCache = new HashMap<JarFile, URL>();
  50 
  51     URLConnection getConnection(JarFile jarFile) throws IOException {
  52         URL u = urlCache.get(jarFile);
  53         if (u != null)
  54             return u.openConnection();
  55 
  56         return null;
  57     }
  58 
  59     public JarFile get(URL url) throws IOException {
  60         return get(url, true);
  61     }
  62 
  63     JarFile get(URL url, boolean useCaches) throws IOException {
  64 
  65         JarFile result = null;
  66         JarFile local_result = null;
  67 
  68         if (useCaches) {
  69             synchronized (this) {
  70                 result = getCachedJarFile(url);
  71             }
  72             if (result == null) {
  73                 local_result = URLJarFile.getJarFile(url, this);
  74                 synchronized (this) {
  75                     result = getCachedJarFile(url);
  76                     if (result == null) {
  77                         fileCache.put(URLUtil.urlNoFragString(url), local_result);
  78                         urlCache.put(local_result, url);
  79                         result = local_result;
  80                     } else {
  81                         if (local_result != null) {
  82                             local_result.close();
  83                         }
  84                     }
  85                 }
  86             }
  87         } else {
  88             result = URLJarFile.getJarFile(url, this);
  89         }
  90         if (result == null)
  91             throw new FileNotFoundException(url.toString());
  92 
  93         return result;
  94     }
  95 
  96     /**
  97      * Callback method of the URLJarFileCloseController to
  98      * indicate that the JarFile is close. This way we can
  99      * remove the JarFile from the cache
 100      */
 101     public void close(JarFile jarFile) {
 102         URL urlRemoved = urlCache.remove(jarFile);
 103         if( urlRemoved != null) {
 104                 fileCache.remove(URLUtil.urlNoFragString(urlRemoved));
 105         }
 106     }
 107 
 108 
 109     private JarFile getCachedJarFile(URL url) {
 110         JarFile result = fileCache.get(URLUtil.urlNoFragString(url));
 111 
 112         /* if the JAR file is cached, the permission will always be there */
 113         if (result != null) {
 114             Permission perm = getPermission(result);
 115             if (perm != null) {
 116                 SecurityManager sm = System.getSecurityManager();
 117                 if (sm != null) {
 118                     try {
 119                         sm.checkPermission(perm);
 120                     } catch (SecurityException se) {
 121                         // fallback to checkRead/checkConnect for pre 1.2
 122                         // security managers
 123                         if ((perm instanceof java.io.FilePermission) &&
 124                             perm.getActions().indexOf("read") != -1) {
 125                             sm.checkRead(perm.getName());
 126                         } else if ((perm instanceof
 127                             java.net.SocketPermission) &&
 128                             perm.getActions().indexOf("connect") != -1) {
 129                             sm.checkConnect(url.getHost(), url.getPort());
 130                         } else {
 131                             throw se;
 132                         }
 133                     }
 134                 }
 135             }
 136         }
 137         return result;
 138     }
 139 
 140     private Permission getPermission(JarFile jarFile) {
 141         try {
 142             URLConnection uc = getConnection(jarFile);
 143             if (uc != null)
 144                 return uc.getPermission();
 145         } catch (IOException ioe) {
 146             // gulp
 147         }
 148 
 149         return null;
 150     }
 151 }