1/*
2 * Copyright (c) 1999, 2013, 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 1.2
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        if (url.getProtocol().equalsIgnoreCase("file")) {
76            // Deal with UNC pathnames specially. See 4180841
77
78            String host = url.getHost();
79            if (host != null && !host.equals("") &&
80                !host.equalsIgnoreCase("localhost")) {
81
82                url = new URL("file", "", "//" + host + url.getPath());
83            }
84        }
85
86        JarFile result;
87        JarFile local_result;
88
89        if (useCaches) {
90            synchronized (instance) {
91                result = getCachedJarFile(url);
92            }
93            if (result == null) {
94                local_result = URLJarFile.getJarFile(url, this);
95                synchronized (instance) {
96                    result = getCachedJarFile(url);
97                    if (result == null) {
98                        fileCache.put(urlKey(url), local_result);
99                        urlCache.put(local_result, url);
100                        result = local_result;
101                    } else {
102                        if (local_result != null) {
103                            local_result.close();
104                        }
105                    }
106                }
107            }
108        } else {
109            result = URLJarFile.getJarFile(url, this);
110        }
111        if (result == null)
112            throw new FileNotFoundException(url.toString());
113
114        return result;
115    }
116
117    /**
118     * Callback method of the URLJarFileCloseController to
119     * indicate that the JarFile is close. This way we can
120     * remove the JarFile from the cache
121     */
122    public void close(JarFile jarFile) {
123        synchronized (instance) {
124            URL urlRemoved = urlCache.remove(jarFile);
125            if (urlRemoved != null)
126                fileCache.remove(urlKey(urlRemoved));
127        }
128    }
129
130    private JarFile getCachedJarFile(URL url) {
131        assert Thread.holdsLock(instance);
132        JarFile result = fileCache.get(urlKey(url));
133
134        /* if the JAR file is cached, the permission will always be there */
135        if (result != null) {
136            Permission perm = getPermission(result);
137            if (perm != null) {
138                SecurityManager sm = System.getSecurityManager();
139                if (sm != null) {
140                    try {
141                        sm.checkPermission(perm);
142                    } catch (SecurityException se) {
143                        // fallback to checkRead/checkConnect for pre 1.2
144                        // security managers
145                        if ((perm instanceof java.io.FilePermission) &&
146                            perm.getActions().indexOf("read") != -1) {
147                            sm.checkRead(perm.getName());
148                        } else if ((perm instanceof
149                            java.net.SocketPermission) &&
150                            perm.getActions().indexOf("connect") != -1) {
151                            sm.checkConnect(url.getHost(), url.getPort());
152                        } else {
153                            throw se;
154                        }
155                    }
156                }
157            }
158        }
159        return result;
160    }
161
162    private String urlKey(URL url) {
163        String urlstr =  URLUtil.urlNoFragString(url);
164        if ("runtime".equals(url.getRef())) urlstr += "#runtime";
165        return urlstr;
166    }
167
168    private Permission getPermission(JarFile jarFile) {
169        try {
170            URLConnection uc = getConnection(jarFile);
171            if (uc != null)
172                return uc.getPermission();
173        } catch (IOException ioe) {
174            // gulp
175        }
176
177        return null;
178    }
179}
180