libjava/java/util/jar/JarEntry.java

   1 /* JarEntry.java - Represents an entry in a jar file
   2    Copyright (C) 2000 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38 package java.util.jar;
  39
  40 import java.io.IOException;
  41 import java.security.cert.Certificate;
  42 import java.util.zip.ZipEntry;
  43
  44 /**
  45  * Extension to a ZipEntry that contains manifest attributes and certificates.
  46  * Both the Atrributes and the Certificates can be null when not set.
  47  * Note that the <code>getCertificates()</code> method only returns a
  48  * valid value after all of the data of the entry has been read.
  49  * <p>
  50  * There are no public methods to set the attributes or certificate of an
  51  * Entru. Only JarEntries created by the classes in <code>java.util.jar</code>
  52  * will have these properties set.
  53  *
  54  * @since 1.2
  55  * @author Mark Wielaard (mark@klomp.org)
  56  */
  57
  58 public class JarEntry extends ZipEntry
  59 {
  60   // (Package local) fields
  61
  62   Attributes attr;
  63   Certificate certs[];
  64
  65   // Constructors
  66
  67   /**
  68    * Creates a new JarEntry with the specified name and no attributes or
  69    * or certificates. Calls <code>super(name)</code> so all other (zip)entry
  70    * fields are null or -1.
  71    *
  72    * @param name the name of the new jar entry
  73    * @exception NullPointerException when the supplied name is null
  74    * @exception IllegalArgumentException when the supplied name is longer
  75    * than 65535 bytes
  76    */
  77   public JarEntry(String name) throws NullPointerException,
  78     IllegalArgumentException
  79   {
  80     super(name);
  81     attr = null;
  82     certs = null;
  83   }
  84
  85   /**
  86    * Creates a new JarEntry with the specified ZipEntry as template for
  87    * all properties of the entry. Both attributes and certificates will be
  88    * null.
  89    *
  90    * @param entry the ZipEntry whose fields should be copied
  91    */
  92   public JarEntry(ZipEntry entry)
  93   {
  94     super(entry);
  95     attr = null;
  96     certs = null;
  97   }
  98
  99   /**
 100    * Creates a new JarEntry with the specified JarEntry as template for
 101    * all properties of the entry.
 102    *
 103    * @param entry the jarEntry whose fields should be copied
 104    */
 105   public JarEntry(JarEntry entry)
 106   {
 107     super(entry);
 108     try
 109       {
 110         attr = entry.getAttributes();
 111       }
 112     catch (IOException _)
 113       {
 114       }
 115     certs = entry.getCertificates();
 116   }
 117
 118   // Methods
 119
 120   /**
 121    * Returns a copy of the Attributes set for this entry.
 122    * When no Attributes are set in the manifest null is returned.
 123    *
 124    * @return a copy of the Attributes set for this entry
 125    * @exception IOException This will never be thrown. It is here for
 126    * binary compatibility.
 127    */
 128   public Attributes getAttributes() throws IOException
 129   {
 130     if (attr != null)
 131       {
 132         return (Attributes) attr.clone();
 133       }
 134     else
 135       {
 136         return null;
 137       }
 138   }
 139
 140   /**
 141    * Returns a copy of the certificates set for this entry.
 142    * When no certificates are set or when not all data of this entry has
 143    * been read null is returned.
 144    * <p>
 145    * To make sure that this call returns a valid value you must read all
 146    * data from the JarInputStream for this entry.
 147    * When you don't need the data for an entry but want to know the
 148    * certificates that are set for the entry then you can skip all data by
 149    * calling <code>skip(entry.getSize())</code> on the JarInputStream for
 150    * the entry.
 151    *
 152    * @return a copy of the certificates set for this entry
 153    */
 154   public Certificate[] getCertificates()
 155   {
 156     if (certs != null)
 157       {
 158         return (Certificate[])certs.clone();
 159       }
 160     else
 161       {
 162         return null;
 163       }
 164   }
 165 }