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 }