1 /* GZIPOutputStream.java - Create a file in gzip format 2 Copyright (C) 1999, 2000, 2001 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.zip; 39 40 import java.io.IOException; 41 import java.io.OutputStream; 42 43 /** 44 * @author Tom Tromey 45 * @date May 17, 1999 46 */ 47 48 /* Written using on-line Java Platform 1.2 API Specification 49 * and JCL book. 50 * Believed complete and correct. 51 */ 52 53 public class GZIPOutputStream extends DeflaterOutputStream 54 { close()55 public void close () throws IOException 56 { 57 finish (); 58 out.close (); 59 } 60 finish()61 public void finish () throws IOException 62 { 63 super.finish(); 64 put4 ((int) crc.getValue()); 65 put4 (def.getTotalIn()); 66 } 67 GZIPOutputStream(OutputStream out)68 public GZIPOutputStream (OutputStream out) throws IOException 69 { 70 this (out, 512); 71 } 72 GZIPOutputStream(OutputStream out, int readsize)73 public GZIPOutputStream (OutputStream out, int readsize) throws IOException 74 { 75 super (out, new Deflater (Deflater.DEFAULT_COMPRESSION, true), readsize); 76 77 put2 (GZIPInputStream.GZIP_MAGIC); 78 out.write (GZIPInputStream.Z_DEFLATED); 79 // No flags for now. 80 out.write (0); 81 // No time either. 82 put2 (0); 83 put2 (0); 84 // No xflags either. 85 out.write (0); 86 // FIXME: unknown OS. 87 out.write (255); 88 89 crc = new CRC32 (); 90 } 91 write(int bval)92 public synchronized void write (int bval) throws IOException 93 { 94 super.write (bval); 95 crc.update (bval); 96 } 97 write(byte[] buf)98 public synchronized void write (byte[] buf) throws IOException 99 { 100 write (buf, 0, buf.length); 101 } 102 write(byte[] buf, int off, int len)103 public synchronized void write (byte[] buf, int off, int len) 104 throws IOException 105 { 106 super.write(buf, off, len); 107 crc.update(buf, off, len); 108 } 109 put2(int i)110 private final void put2 (int i) throws IOException 111 { 112 out.write (i); 113 out.write (i >> 8); 114 } 115 put4(int i)116 private final void put4 (int i) throws IOException 117 { 118 out.write (i); 119 out.write (i >> 8); 120 out.write (i >> 16); 121 out.write (i >> 24); 122 } 123 124 // Checksum used by this stream. 125 protected CRC32 crc; 126 } 127