001/* Manifest.java -- Reads, writes and manipulates jar manifest files
002   Copyright (C) 2000, 2004 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038package java.util.jar;
039
040import gnu.java.util.jar.JarUtils;
041
042import java.io.IOException;
043import java.io.InputStream;
044import java.io.OutputStream;
045import java.util.Hashtable;
046import java.util.Map;
047
048/**
049 * Reads, writes and manipulaties jar manifest files.
050 * XXX
051 *
052 * @since 1.2
053 * @author Mark Wielaard (mark@klomp.org)
054 */
055public class Manifest implements Cloneable
056{
057  // Fields
058
059  /** The main attributes of the manifest (jar file). */
060  private final Attributes mainAttr;
061
062  /** A map of atrributes for all entries described in this Manifest. */
063  private final Map<String, Attributes> entries;
064
065  // Constructors
066
067  /**
068   * Creates a new empty Manifest.
069   */
070  public Manifest()
071  {
072    mainAttr = new Attributes();
073    entries = new Hashtable<String, Attributes>();
074  }
075
076  /**
077   * Creates a Manifest from the supplied input stream.
078   *
079   * @see #read(InputStream)
080   * @see #write(OutputStream)
081   *
082   * @param in the input stream to read the manifest from
083   * @exception IOException when an i/o exception occurs or the input stream
084   * does not describe a valid manifest
085   */
086  public Manifest(InputStream in) throws IOException
087  {
088    this();
089    read(in);
090  }
091
092  /**
093   * Creates a Manifest from another Manifest.
094   * Makes a deep copy of the main attributes, but a shallow copy of
095   * the other entries. This means that you can freely add, change or remove
096   * the main attributes or the entries of the new manifest without effecting
097   * the original manifest, but adding, changing or removing attributes from
098   * a particular entry also changes the attributes of that entry in the
099   * original manifest.
100   *
101   * @see #clone()
102   * @param man the Manifest to copy from
103   */
104  public Manifest(Manifest man)
105  {
106    mainAttr = new Attributes(man.getMainAttributes());
107    entries = new Hashtable<String, Attributes>(man.getEntries());
108  }
109
110  // Methods
111
112  /**
113   * Gets the main attributes of this Manifest.
114   */
115  public Attributes getMainAttributes()
116  {
117    return mainAttr;
118  }
119
120  /**
121   * Gets a map of entry Strings to Attributes for all the entries described
122   * in this manifest. Adding, changing or removing from this entries map
123   * changes the entries of this manifest.
124   */
125  public Map<String, Attributes> getEntries()
126  {
127    return entries;
128  }
129
130  /**
131   * Returns the Attributes associated with the Entry.
132   * <p>
133   * Implemented as:
134   * <code>return (Attributes)getEntries().get(entryName)</code>
135   *
136   * @param entryName the name of the entry to look up
137   * @return the attributes associated with the entry or null when none
138   */
139  public Attributes getAttributes(String entryName)
140  {
141    return getEntries().get(entryName);
142  }
143
144  /**
145   * Clears the main attributes and removes all the entries from the
146   * manifest.
147   */
148  public void clear()
149  {
150    mainAttr.clear();
151    entries.clear();
152  }
153
154  /**
155   * Read and merge a <code>Manifest</code> from the designated input stream.
156   *
157   * @param in the input stream to read from.
158   * @throws IOException if an I/O related exception occurs during the process.
159   */
160  public void read(InputStream in) throws IOException
161  {
162    JarUtils.readMFManifest(getMainAttributes(), getEntries(), in);
163  }
164
165  /**
166   * Writes the contents of this <code>Manifest</code> to the designated
167   * output stream. Line-endings are platform-independent and consist of the
168   * 2-codepoint sequence <code>0x0D</code> and <code>0x0A</code>.
169   *
170   * @param out the output stream to write this <code>Manifest</code> to.
171   * @throws IOException if an I/O related exception occurs during the process.
172   */
173  public void write(OutputStream out) throws IOException
174  {
175    JarUtils.writeMFManifest(getMainAttributes(), getEntries(), out);
176  }
177
178  /**
179   * Makes a deep copy of the main attributes, but a shallow copy of
180   * the other entries. This means that you can freely add, change or remove
181   * the main attributes or the entries of the new manifest without effecting
182   * the original manifest, but adding, changing or removing attributes from
183   * a particular entry also changes the attributes of that entry in the
184   * original manifest. Calls <CODE>new Manifest(this)</CODE>.
185   */
186  public Object clone()
187  {
188    return new Manifest(this);
189  }
190
191  /**
192   * Checks if another object is equal to this Manifest object.
193   * Another Object is equal to this Manifest object if it is an instance of
194   * Manifest and the main attributes and the entries of the other manifest
195   * are equal to this one.
196   */
197  public boolean equals(Object o)
198  {
199    return (o instanceof Manifest) &&
200      (mainAttr.equals(((Manifest) o).mainAttr)) &&
201      (entries.equals(((Manifest) o).entries));
202  }
203
204  /**
205   * Calculates the hash code of the manifest. Implemented by a xor of the
206   * hash code of the main attributes with the hash code of the entries map.
207   */
208  public int hashCode()
209  {
210    return mainAttr.hashCode() ^ entries.hashCode();
211  }
212
213}