jdk/test/java/rmi/server/RMISocketFactory/useSocketFactory/activatable/CompressOutputStream.java

/* 
 * Copyright 1998 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

/*
 */

import java.io.*;

class CompressOutputStream extends FilterOutputStream
    implements CompressConstants
{

    public CompressOutputStream(OutputStream out) {
	super(out);
    }

    // buffer of 6-bit codes to pack into next 32-bit word
    int buf[] = new int[5];

    // number of valid codes pending in buffer
    int bufPos = 0;

    public void write(int b) throws IOException {
	b &= 0xFF;			// force argument to a byte

	int pos = codeTable.indexOf((char)b);
	if (pos != -1)
	    writeCode(BASE + pos);
	else {
	    writeCode(RAW);
	    writeCode(b >> 4);
	    writeCode(b & 0xF);
	}
    }

    public void write(byte b[], int off, int len) throws IOException {
	/*
	 * This is quite an inefficient implementation, because it has to
	 * call the other write method for every byte in the array.  It
         * could be optimized for performance by doing all the processing
	 * in this method.
	 */
	for (int i = 0; i < len; i++)
	    write(b[off + i]);
    }

    public void flush() throws IOException {
	while (bufPos > 0)
	    writeCode(NOP);
    }

    private void writeCode(int c) throws IOException {
	buf[bufPos++] = c;
	if (bufPos == 5) {	// write next word when we have 5 codes
	    int pack = (buf[0] << 24) | (buf[1] << 18) | (buf[2] << 12) |
	               (buf[3] << 6) | buf[4];
	    out.write((pack >>> 24) & 0xFF);
	    out.write((pack >>> 16) & 0xFF);
	    out.write((pack >>> 8)  & 0xFF);
	    out.write((pack >>> 0)  & 0xFF);
	    bufPos = 0;
	}
    }
}