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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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).
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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 final HashMap<String, JarFile> fileCache = new HashMap<>();
47 
48     /* the file to url cache */
49     private static final HashMap<JarFile, URL> urlCache = new HashMap<>();
50 
51     private static final JarFileFactory instance = new JarFileFactory();
52 
JarFileFactory()53     private JarFileFactory() { }
54 
getInstance()55     public static JarFileFactory getInstance() {
56         return instance;
57     }
58 
getConnection(JarFile jarFile)59     URLConnection getConnection(JarFile jarFile) throws IOException {
60         URL u;
61         synchronized (instance) {
62             u = urlCache.get(jarFile);
63         }
64         if (u != null)
65             return u.openConnection();
66 
67         return null;
68     }
69 
get(URL url)70     public JarFile get(URL url) throws IOException {
71         return get(url, true);
72     }
73 
get(URL url, boolean useCaches)74     JarFile get(URL url, boolean useCaches) throws IOException {
75 
76         JarFile result;
77         JarFile local_result;
78 
79         if (useCaches) {
80             synchronized (instance) {
81                 result = getCachedJarFile(url);
82             }
83             if (result == null) {
84                 local_result = URLJarFile.getJarFile(url, this);
85                 synchronized (instance) {
86                     result = getCachedJarFile(url);
87                     if (result == null) {
88                         fileCache.put(URLUtil.urlNoFragString(url), local_result);
89                         urlCache.put(local_result, url);
90                         result = local_result;
91                     } else {
92                         if (local_result != null) {
93                             local_result.close();
94                         }
95                     }
96                 }
97             }
98         } else {
99             result = URLJarFile.getJarFile(url, this);
100         }
101         if (result == null)
102             throw new FileNotFoundException(url.toString());
103 
104         return result;
105     }
106 
107     /**
108      * Callback method of the URLJarFileCloseController to
109      * indicate that the JarFile is close. This way we can
110      * remove the JarFile from the cache
111      */
close(JarFile jarFile)112     public void close(JarFile jarFile) {
113         synchronized (instance) {
114             URL urlRemoved = urlCache.remove(jarFile);
115             if (urlRemoved != null)
116                 fileCache.remove(URLUtil.urlNoFragString(urlRemoved));
117         }
118     }
119 
getCachedJarFile(URL url)120     private JarFile getCachedJarFile(URL url) {
121         assert Thread.holdsLock(instance);
122         JarFile result = fileCache.get(URLUtil.urlNoFragString(url));
123 
124         /* if the JAR file is cached, the permission will always be there */
125         if (result != null) {
126             Permission perm = getPermission(result);
127             if (perm != null) {
128                 SecurityManager sm = System.getSecurityManager();
129                 if (sm != null) {
130                     try {
131                         sm.checkPermission(perm);
132                     } catch (SecurityException se) {
133                         // fallback to checkRead/checkConnect for pre 1.2
134                         // security managers
135                         if ((perm instanceof java.io.FilePermission) &&
136                             perm.getActions().indexOf("read") != -1) {
137                             sm.checkRead(perm.getName());
138                         } else if ((perm instanceof
139                             java.net.SocketPermission) &&
140                             perm.getActions().indexOf("connect") != -1) {
141                             sm.checkConnect(url.getHost(), url.getPort());
142                         } else {
143                             throw se;
144                         }
145                     }
146                 }
147             }
148         }
149         return result;
150     }
151 
getPermission(JarFile jarFile)152     private Permission getPermission(JarFile jarFile) {
153         try {
154             URLConnection uc = getConnection(jarFile);
155             if (uc != null)
156                 return uc.getPermission();
157         } catch (IOException ioe) {
158             // gulp
159         }
160 
161         return null;
162     }
163 }
164