Source for java.util.zip.CheckedOutputStream

   1: /* CheckedOutputStream.java - Compute checksum of data being written.
   2:    Copyright (C) 1999, 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., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 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 java.util.zip;
  40: 
  41: import java.io.FilterOutputStream;
  42: import java.io.IOException;
  43: import java.io.OutputStream;
  44: 
  45: /* Written using on-line Java Platform 1.2 API Specification
  46:  * and JCL book.
  47:  * Believed complete and correct.
  48:  */
  49: 
  50: /**
  51:  * OutputStream that computes a checksum of data being written using a
  52:  * supplied Checksum object.
  53:  *
  54:  * @see Checksum
  55:  *
  56:  * @author Tom Tromey
  57:  * @date May 17, 1999
  58:  */
  59: public class CheckedOutputStream extends FilterOutputStream
  60: {
  61:   /**
  62:    * Creates a new CheckInputStream on top of the supplied OutputStream
  63:    * using the supplied Checksum.
  64:    */
  65:   public CheckedOutputStream (OutputStream out, Checksum cksum)
  66:   {
  67:     super (out);
  68:     this.sum = cksum;
  69:   }
  70: 
  71:   /**
  72:    * Returns the Checksum object used. To get the data checksum computed so
  73:    * far call <code>getChecksum.getValue()</code>.
  74:    */
  75:   public Checksum getChecksum ()
  76:   {
  77:     return sum;
  78:   }
  79: 
  80:   /**
  81:    * Writes one byte to the OutputStream and updates the Checksum.
  82:    */
  83:   public void write (int bval) throws IOException
  84:   {
  85:     out.write(bval);
  86:     sum.update(bval);
  87:   }
  88: 
  89:   /**
  90:    * Writes the byte array to the OutputStream and updates the Checksum.
  91:    */
  92:   public void write (byte[] buf, int off, int len) throws IOException
  93:   {
  94:     out.write(buf, off, len);
  95:     sum.update(buf, off, len);
  96:   }
  97: 
  98:   /** The checksum object. */
  99:   private Checksum sum;
 100: }