1 /*
2 * Copyright 1997-2006 Sun Microsystems, Inc. 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. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 package java.net;
27
28 import java.io.IOException;
29 import java.util.jar.JarFile;
30 import java.util.jar.JarEntry;
31 import java.util.jar.Attributes;
32 import java.util.jar.Manifest;
33 import java.security.Permission;
34 import sun.net.www.ParseUtil;
35
36 /**
37 * A URL Connection to a Java ARchive (JAR) file or an entry in a JAR
38 * file.
39 *
40 * <p>The syntax of a JAR URL is:
41 *
42 * <pre>
43 * jar:<url>!/{entry}
44 * </pre>
45 *
46 * <p>for example:
47 *
48 * <p><code>
49 * jar:http://www.foo.com/bar/baz.jar!/COM/foo/Quux.class<br>
50 * </code>
51 *
52 * <p>Jar URLs should be used to refer to a JAR file or entries in
53 * a JAR file. The example above is a JAR URL which refers to a JAR
54 * entry. If the entry name is omitted, the URL refers to the whole
55 * JAR file:
56 *
57 * <code>
58 * jar:http://www.foo.com/bar/baz.jar!/
59 * </code>
60 *
61 * <p>Users should cast the generic URLConnection to a
62 * JarURLConnection when they know that the URL they created is a JAR
63 * URL, and they need JAR-specific functionality. For example:
64 *
65 * <pre>
66 * URL url = new URL("jar:file:/home/duke/duke.jar!/");
67 * JarURLConnection jarConnection = (JarURLConnection)url.openConnection();
68 * Manifest manifest = jarConnection.getManifest();
69 * </pre>
70 *
71 * <p>JarURLConnection instances can only be used to read from JAR files.
72 * It is not possible to get a {@link java.io.OutputStream} to modify or write
73 * to the underlying JAR file using this class.
74 * <p>Examples:
75 *
76 * <dl>
77 *
78 * <dt>A Jar entry
79 * <dd><code>jar:http://www.foo.com/bar/baz.jar!/COM/foo/Quux.class</code>
80 *
81 * <dt>A Jar file
82 * <dd><code>jar:http://www.foo.com/bar/baz.jar!/</code>
83 *
84 * <dt>A Jar directory
85 * <dd><code>jar:http://www.foo.com/bar/baz.jar!/COM/foo/</code>
86 *
87 * </dl>
88 *
89 * <p><code>!/</code> is refered to as the <em>separator</em>.
90 *
91 * <p>When constructing a JAR url via <code>new URL(context, spec)</code>,
92 * the following rules apply:
93 *
94 * <ul>
95 *
96 * <li>if there is no context URL and the specification passed to the
97 * URL constructor doesn't contain a separator, the URL is considered
98 * to refer to a JarFile.
99 *
100 * <li>if there is a context URL, the context URL is assumed to refer
101 * to a JAR file or a Jar directory.
102 *
103 * <li>if the specification begins with a '/', the Jar directory is
104 * ignored, and the spec is considered to be at the root of the Jar
105 * file.
106 *
107 * <p>Examples:
108 *
109 * <dl>
110 *
111 * <dt>context: <b>jar:http://www.foo.com/bar/jar.jar!/</b>,
112 * spec:<b>baz/entry.txt</b>
113 *
114 * <dd>url:<b>jar:http://www.foo.com/bar/jar.jar!/baz/entry.txt</b>
115 *
116 * <dt>context: <b>jar:http://www.foo.com/bar/jar.jar!/baz</b>,
117 * spec:<b>entry.txt</b>
118 *
119 * <dd>url:<b>jar:http://www.foo.com/bar/jar.jar!/baz/entry.txt</b>
120 *
121 * <dt>context: <b>jar:http://www.foo.com/bar/jar.jar!/baz</b>,
122 * spec:<b>/entry.txt</b>
123 *
124 * <dd>url:<b>jar:http://www.foo.com/bar/jar.jar!/entry.txt</b>
125 *
126 * </dl>
127 *
128 * </ul>
129 *
130 * @see java.net.URL
131 * @see java.net.URLConnection
132 *
133 * @see java.util.jar.JarFile
134 * @see java.util.jar.JarInputStream
135 * @see java.util.jar.Manifest
136 * @see java.util.zip.ZipEntry
137 *
138 * @author Benjamin Renaud
139 * @since 1.2
140 */
141 public abstract class JarURLConnection extends URLConnection {
142
143 private URL jarFileURL;
144 private String entryName;
145
146 /**
147 * The connection to the JAR file URL, if the connection has been
148 * initiated. This should be set by connect.
149 */
150 protected URLConnection jarFileURLConnection;
151
152 /**
153 * Creates the new JarURLConnection to the specified URL.
154 * @param url the URL
155 * @throws MalformedURLException if no legal protocol
156 * could be found in a specification string or the
157 * string could not be parsed.
158 */
159
160 protected JarURLConnection(URL url) throws MalformedURLException {
161 super(url);
162 parseSpecs(url);
163 }
164
165 /* get the specs for a given url out of the cache, and compute and
166 * cache them if they're not there.
167 */
168 private void parseSpecs(URL url) throws MalformedURLException {
169 String spec = url.getFile();
170
171 int separator = spec.indexOf("!/");
172 /*
173 * REMIND: we don't handle nested JAR URLs
174 */
175 if (separator == -1) {
176 throw new MalformedURLException("no !/ found in url spec:" + spec);
177 }
178
179 jarFileURL = new URL(spec.substring(0, separator++));
180 entryName = null;
181
182 /* if ! is the last letter of the innerURL, entryName is null */
183 if (++separator != spec.length()) {
184 entryName = spec.substring(separator, spec.length());
185 entryName = ParseUtil.decode (entryName);
186 }
187 }
188
189 /**
190 * Returns the URL for the Jar file for this connection.
191 *
192 * @return the URL for the Jar file for this connection.
193 */
194 public URL getJarFileURL() {
195 return jarFileURL;
196 }
197
198 /**
199 * Return the entry name for this connection. This method
200 * returns null if the JAR file URL corresponding to this
201 * connection points to a JAR file and not a JAR file entry.
202 *
203 * @return the entry name for this connection, if any.
204 */
205 public String getEntryName() {
206 return entryName;
207 }
208
209 /**
210 * Return the JAR file for this connection.
211 *
212 * @return the JAR file for this connection. If the connection is
213 * a connection to an entry of a JAR file, the JAR file object is
214 * returned
215 *
216 * @exception IOException if an IOException occurs while trying to
217 * connect to the JAR file for this connection.
218 *
219 * @see #connect
220 */
221 public abstract JarFile getJarFile() throws IOException;
222
223 /**
224 * Returns the Manifest for this connection, or null if none.
225 *
226 * @return the manifest object corresponding to the JAR file object
227 * for this connection.
228 *
229 * @exception IOException if getting the JAR file for this
230 * connection causes an IOException to be trown.
231 *
232 * @see #getJarFile
233 */
234 public Manifest getManifest() throws IOException {
235 return getJarFile().getManifest();
236 }
237
238 /**
239 * Return the JAR entry object for this connection, if any. This
240 * method returns null if the JAR file URL corresponding to this
241 * connection points to a JAR file and not a JAR file entry.
242 *
243 * @return the JAR entry object for this connection, or null if
244 * the JAR URL for this connection points to a JAR file.
245 *
246 * @exception IOException if getting the JAR file for this
247 * connection causes an IOException to be trown.
248 *
249 * @see #getJarFile
250 * @see #getJarEntry
251 */
252 public JarEntry getJarEntry() throws IOException {
253 return getJarFile().getJarEntry(entryName);
254 }
255
256 /**
257 * Return the Attributes object for this connection if the URL
258 * for it points to a JAR file entry, null otherwise.
259 *
260 * @return the Attributes object for this connection if the URL
261 * for it points to a JAR file entry, null otherwise.
262 *
263 * @exception IOException if getting the JAR entry causes an
264 * IOException to be thrown.
265 *
266 * @see #getJarEntry
267 */
268 public Attributes getAttributes() throws IOException {
269 JarEntry e = getJarEntry();
270 return e != null ? e.getAttributes() : null;
271 }
272
273 /**
274 * Returns the main Attributes for the JAR file for this
275 * connection.
276 *
277 * @return the main Attributes for the JAR file for this
278 * connection.
279 *
280 * @exception IOException if getting the manifest causes an
281 * IOException to be thrown.
282 *
283 * @see #getJarFile
284 * @see #getManifest
285 */
286 public Attributes getMainAttributes() throws IOException {
287 Manifest man = getManifest();
288 return man != null ? man.getMainAttributes() : null;
289 }
290
291 /**
292 * Return the Certificate object for this connection if the URL
293 * for it points to a JAR file entry, null otherwise. This method
294 * can only be called once
295 * the connection has been completely verified by reading
296 * from the input stream until the end of the stream has been
297 * reached. Otherwise, this method will return <code>null</code>
298 *
299 * @return the Certificate object for this connection if the URL
300 * for it points to a JAR file entry, null otherwise.
301 *
302 * @exception IOException if getting the JAR entry causes an
303 * IOException to be thrown.
304 *
305 * @see #getJarEntry
306 */
307 public java.security.cert.Certificate[] getCertificates()
308 throws IOException
309 {
310 JarEntry e = getJarEntry();
311 return e != null ? e.getCertificates() : null;
312 }
313 }
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