1 /* DeflaterOutputStream.java - Output filter for compressing.
2 Copyright (C) 1999, 2000, 2001, 2004 Free Software Foundation, Inc.
4 This file is part of GNU Classpath.
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)
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.
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
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
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. */
39 package java.util.zip;
41 import java.io.FilterOutputStream;
42 import java.io.IOException;
43 import java.io.OutputStream;
45 /* Written using on-line Java Platform 1.2 API Specification
47 * Believed complete and correct.
51 * This is a special FilterOutputStream deflating the bytes that are
52 * written through it. It uses the Deflater for deflating.
54 * A special thing to be noted is that flush() doesn't flush
55 * everything in Sun's JDK, but it does so in jazzlib. This is because
56 * Sun's Deflater doesn't have a way to flush() everything, without
57 * finishing the stream.
59 * @author Tom Tromey, Jochen Hoenicke
62 public class DeflaterOutputStream extends FilterOutputStream
65 * This buffer is used temporarily to retrieve the bytes from the
66 * deflater and write them to the underlying output stream.
71 * The deflater which is used to deflate the stream.
73 protected Deflater def;
76 * Deflates everything in the def's input buffers. This will call
77 * <code>def.deflate()</code> until all bytes from the input buffers
80 protected void deflate() throws IOException
82 while (! def.needsInput())
84 int len = def.deflate(buf, 0, buf.length);
86 out.write(buf, 0, len);
91 * Creates a new DeflaterOutputStream with a default Deflater and
92 * default buffer size.
93 * @param out the output stream where deflated output should be written.
95 public DeflaterOutputStream(OutputStream out)
97 this(out, new Deflater(), 512);
101 * Creates a new DeflaterOutputStream with the given Deflater and
102 * default buffer size.
103 * @param out the output stream where deflated output should be written.
104 * @param defl the underlying deflater.
106 public DeflaterOutputStream(OutputStream out, Deflater defl)
108 this(out, defl, 512);
112 * Creates a new DeflaterOutputStream with the given Deflater and
114 * @param out the output stream where deflated output should be written.
115 * @param defl the underlying deflater.
116 * @param bufsize the buffer size.
117 * @exception IllegalArgumentException if bufsize isn't positive.
119 public DeflaterOutputStream(OutputStream out, Deflater defl, int bufsize)
123 throw new IllegalArgumentException("bufsize <= 0");
124 buf = new byte[bufsize];
129 * Finishes the stream by calling finish() on the deflater. This
130 * was the only way to ensure that all bytes are flushed in Sun's
133 public void finish() throws IOException
137 while (! def.finished())
139 int len = def.deflate(buf, 0, buf.length);
141 out.write(buf, 0, len);
146 * Calls finish() and closes the stream.
148 public void close() throws IOException
155 * Writes a single byte to the compressed output stream.
156 * @param bval the byte value.
158 public void write(int bval) throws IOException
161 inbuf = new byte[128];
162 else if (inbufLength == inbuf.length)
164 inbuf[inbufLength++] = (byte) bval;
168 * Writes a len bytes from an array to the compressed stream.
169 * @param buf the byte array.
170 * @param off the offset into the byte array where to start.
171 * @param len the number of bytes to write.
173 public void write(byte[] buf, int off, int len) throws IOException
176 def.setInput(buf, off, len);
180 private void inbufWrite() throws IOException
184 int size = inbufLength;
186 write(inbuf, 0, size);
190 // Used, if needed, for write(int).
191 private byte[] inbuf;
192 // Used length of inbuf.
193 private int inbufLength;