1 /* DeflaterOutputStream.java - Output filter for compressing. 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., 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.FilterOutputStream; 41 import java.io.OutputStream; 42 import java.io.IOException; 43 44 /* Written using on-line Java Platform 1.2 API Specification 45 * and JCL book. 46 * Believed complete and correct. 47 */ 48 49 /** 50 * This is a special FilterOutputStream deflating the bytes that are 51 * written through it. It uses the Deflater for deflating. 52 * 53 * A special thing to be noted is that flush() doesn't flush 54 * everything in Sun's JDK, but it does so in jazzlib. This is because 55 * Sun's Deflater doesn't have a way to flush() everything, without 56 * finishing the stream. 57 * 58 * @author Tom Tromey, Jochen Hoenicke 59 * @date Jan 11, 2001 60 */ 61 public class DeflaterOutputStream extends FilterOutputStream 62 { close()63 public void close () throws IOException 64 { 65 finish (); 66 out.close(); 67 } 68 69 /** 70 * Deflates everything in the def's input buffers. This will call 71 * <code>def.deflate()</code> until all bytes from the input buffers 72 * are processed. 73 */ deflate()74 protected void deflate () throws IOException 75 { 76 do 77 { 78 int len = def.deflate(buf, 0, buf.length); 79 if (len > 0) 80 out.write(buf, 0, len); 81 } 82 while (! def.needsInput()); 83 } 84 85 /** 86 * Creates a new DeflaterOutputStream with a default Deflater and 87 * default buffer size. 88 * @param out the output stream where deflated output should be written. 89 */ DeflaterOutputStream(OutputStream out)90 public DeflaterOutputStream (OutputStream out) 91 { 92 this (out, new Deflater (), 512); 93 } 94 95 /** 96 * Creates a new DeflaterOutputStream with the given Deflater and 97 * default buffer size. 98 * @param out the output stream where deflated output should be written. 99 * @param defl the underlying deflater. 100 */ DeflaterOutputStream(OutputStream out, Deflater defl)101 public DeflaterOutputStream (OutputStream out, Deflater defl) 102 { 103 this (out, defl, 512); 104 } 105 106 /** 107 * Creates a new DeflaterOutputStream with the given Deflater and 108 * buffer size. 109 * @param out the output stream where deflated output should be written. 110 * @param defl the underlying deflater. 111 * @param bufsize the buffer size. 112 * @exception IllegalArgumentException if bufsize isn't positive. 113 */ DeflaterOutputStream(OutputStream out, Deflater defl, int bufsize)114 public DeflaterOutputStream(OutputStream out, Deflater defl, int bufsize) 115 { 116 super (out); 117 if (bufsize <= 0) 118 throw new IllegalArgumentException("bufsize <= 0"); 119 buf = new byte[bufsize]; 120 def = defl; 121 } 122 123 /** 124 * Finishes the stream by calling finish() on the deflater. This 125 * was the only way to ensure that all bytes are flushed in Sun's 126 * JDK. 127 */ finish()128 public void finish () throws IOException 129 { 130 inbufWrite(); 131 def.finish(); 132 while (! def.finished ()) 133 { 134 int len = def.deflate(buf, 0, buf.length); 135 if (len > 0) 136 out.write(buf, 0, len); 137 } 138 } 139 write(int bval)140 public void write (int bval) throws IOException 141 { 142 if (inbuf == null) 143 inbuf = new byte[128]; 144 else if (inbufLength == inbuf.length) 145 inbufWrite (); 146 inbuf[inbufLength++] = (byte) bval; 147 } 148 write(byte[] buf, int off, int len)149 public void write (byte[] buf, int off, int len) throws IOException 150 { 151 inbufWrite (); 152 def.setInput (buf, off, len); 153 deflate (); 154 } 155 inbufWrite()156 private void inbufWrite () throws IOException 157 { 158 if (inbufLength > 0) 159 { 160 int size = inbufLength; 161 inbufLength = 0; 162 write (inbuf, 0, size); 163 } 164 } 165 166 // Used, if needed, for write(int). 167 private byte[] inbuf; 168 // Used length of inbuf. 169 private int inbufLength; 170 171 // The retrieval buffer. 172 protected byte[] buf; 173 174 // Deflater used to compress data. 175 protected Deflater def; 176 } 177