Source for gnu.javax.crypto.keyring.CompressedEntry

   1: /* CompressedEntry.java --
   2:    Copyright (C) 2003, 2006 Free Software Foundation, Inc.
   3: 
   4: This file is a 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 of the License, or (at
   9: your option) 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; if not, write to the Free Software
  18: Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
  19: 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: 
  39: package gnu.javax.crypto.keyring;
  40: 
  41: import java.io.ByteArrayOutputStream;
  42: import java.io.DataInputStream;
  43: import java.io.DataOutputStream;
  44: import java.io.IOException;
  45: import java.util.Iterator;
  46: import java.util.zip.DeflaterOutputStream;
  47: import java.util.zip.InflaterInputStream;
  48: 
  49: public class CompressedEntry
  50:     extends EnvelopeEntry
  51: {
  52:   public static final int TYPE = 4;
  53: 
  54:   public CompressedEntry(Properties properties)
  55:   {
  56:     super(TYPE, properties);
  57:     this.properties.put("algorithm", "DEFLATE");
  58:   }
  59: 
  60:   private CompressedEntry()
  61:   {
  62:     this(new Properties());
  63:   }
  64: 
  65:   public static CompressedEntry decode(DataInputStream in) throws IOException
  66:   {
  67:     CompressedEntry entry = new CompressedEntry();
  68:     entry.properties.decode(in);
  69:     String alg = entry.properties.get("algorithm");
  70:     if (alg == null)
  71:       throw new MalformedKeyringException("no compression algorithm");
  72:     if (! alg.equalsIgnoreCase("DEFLATE"))
  73:       throw new MalformedKeyringException("unsupported compression algorithm: "
  74:                                           + alg);
  75:     int len = in.readInt();
  76:     MeteredInputStream min = new MeteredInputStream(in, len);
  77:     InflaterInputStream infin = new InflaterInputStream(min);
  78:     DataInputStream in2 = new DataInputStream(infin);
  79:     entry.decodeEnvelope(in2);
  80:     return entry;
  81:   }
  82: 
  83:   protected void encodePayload() throws IOException
  84:   {
  85:     ByteArrayOutputStream buf = new ByteArrayOutputStream(1024);
  86:     DeflaterOutputStream dout = new DeflaterOutputStream(buf);
  87:     DataOutputStream out2 = new DataOutputStream(dout);
  88:     for (Iterator it = entries.iterator(); it.hasNext();)
  89:       ((Entry) it.next()).encode(out2);
  90:     dout.finish();
  91:     payload = buf.toByteArray();
  92:   }
  93: }