Initial revision

From-SVN: r102074

libjava/classpath/java/util/zip/DeflaterOutputStream.java

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+/* DeflaterOutputStream.java - Output filter for compressing.
+   Copyright (C) 1999, 2000, 2001, 2004 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package java.util.zip;
+
+import java.io.FilterOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+
+/* Written using on-line Java Platform 1.2 API Specification
+ * and JCL book.
+ * Believed complete and correct.
+ */
+
+/**
+ * This is a special FilterOutputStream deflating the bytes that are
+ * written through it.  It uses the Deflater for deflating.
+ *
+ * A special thing to be noted is that flush() doesn't flush
+ * everything in Sun's JDK, but it does so in jazzlib. This is because
+ * Sun's Deflater doesn't have a way to flush() everything, without
+ * finishing the stream.
+ *
+ * @author Tom Tromey, Jochen Hoenicke
+ * @date Jan 11, 2001 
+ */
+public class DeflaterOutputStream extends FilterOutputStream
+{
+  /** 
+   * This buffer is used temporarily to retrieve the bytes from the
+   * deflater and write them to the underlying output stream.  
+   */
+  protected byte[] buf;
+
+  /** 
+   * The deflater which is used to deflate the stream.
+   */
+  protected Deflater def;
+  
+  /**
+   * Deflates everything in the def's input buffers.  This will call
+   * <code>def.deflate()</code> until all bytes from the input buffers
+   * are processed.
+   */
+  protected void deflate() throws IOException
+  {
+    while (! def.needsInput())
+      {
+	int len = def.deflate(buf, 0, buf.length);
+
+	//	System.err.println("DOS deflated " + len + " out of " + buf.length);
+	if (len <= 0)
+	  break;
+	out.write(buf, 0, len);
+      }
+
+    if (! def.needsInput())
+      throw new InternalError("Can't deflate all input?");
+  }
+
+  /** 
+   * Creates a new DeflaterOutputStream with a default Deflater and
+   * default buffer size.
+   * @param out the output stream where deflated output should be written.
+   */
+  public DeflaterOutputStream(OutputStream out)
+  {
+    this(out, new Deflater(), 512);
+  }
+
+  /** 
+   * Creates a new DeflaterOutputStream with the given Deflater and
+   * default buffer size.
+   * @param out the output stream where deflated output should be written.
+   * @param defl the underlying deflater.
+   */
+  public DeflaterOutputStream(OutputStream out, Deflater defl)
+  {
+    this(out, defl, 512);
+  }
+
+  /** 
+   * Creates a new DeflaterOutputStream with the given Deflater and
+   * buffer size.
+   * @param out the output stream where deflated output should be written.
+   * @param defl the underlying deflater.
+   * @param bufsize the buffer size.
+   * @exception IllegalArgumentException if bufsize isn't positive.
+   */
+  public DeflaterOutputStream(OutputStream out, Deflater defl, int bufsize)
+  {
+    super(out);
+    if (bufsize <= 0)
+      throw new IllegalArgumentException("bufsize <= 0");
+    buf = new byte[bufsize];
+    def = defl;
+  }
+
+  /**  
+   * Flushes the stream by calling flush() on the deflater and then
+   * on the underlying stream.  This ensures that all bytes are
+   * flushed.  This function doesn't work in Sun's JDK, but only in
+   * jazzlib.
+   */
+  public void flush() throws IOException
+  {
+    def.flush();
+    deflate();
+    out.flush();
+  }
+
+  /**
+   * Finishes the stream by calling finish() on the deflater.  This
+   * was the only way to ensure that all bytes are flushed in Sun's
+   * JDK.  
+   */
+  public void finish() throws IOException
+  {
+    def.finish();
+    while (! def.finished())
+      {
+	int len = def.deflate(buf, 0, buf.length);
+	if (len <= 0)
+	  break;
+	out.write(buf, 0, len);
+      }
+    if (! def.finished())
+      throw new InternalError("Can't deflate all input?");
+    out.flush();
+  }
+
+  /**
+   * Calls finish() and closes the stream. 
+   */
+  public void close() throws IOException
+  {
+    finish();
+    out.close();
+  }
+
+  /**
+   * Writes a single byte to the compressed output stream.
+   * @param bval the byte value.
+   */
+  public void write(int bval) throws IOException
+  {
+    byte[] b = new byte[1];
+    b[0] = (byte) bval;
+    write(b, 0, 1);
+  }
+
+  /**
+   * Writes a len bytes from an array to the compressed stream.
+   * @param buf the byte array.
+   * @param off the offset into the byte array where to start.
+   * @param len the number of bytes to write.
+   */
+  public void write(byte[] buf, int off, int len) throws IOException
+  {
+    def.setInput(buf, off, len);
+    deflate();
+  }
+}