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
26package sun.net.www.protocol.jar;
27
28import java.io.IOException;
29import java.io.FileNotFoundException;
30import java.net.URL;
31import java.net.URLConnection;
32import java.util.HashMap;
33import java.util.jar.JarFile;
34import java.security.Permission;
35import 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 */
43class 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
53    private JarFileFactory() { }
54
55    public static JarFileFactory getInstance() {
56        return instance;
57    }
58
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
70    public JarFile get(URL url) throws IOException {
71        return get(url, true);
72    }
73
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     */
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
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
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