Quadcap Embeddable Server

com/quadcap/io/LogOutputStream.java

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package com.quadcap.io;

/* Copyright 1997 - 2003 Quadcap Software.  All rights reserved.
 *
 * This software is distributed under the Quadcap Free Software License.
 * This software may be used or modified for any purpose, personal or
 * commercial.  Open Source redistributions are permitted.  Commercial
 * redistribution of larger works derived from, or works which bundle
 * this software requires a "Commercial Redistribution License"; see
 * http://www.quadcap.com/purchase.
 *
 * Redistributions qualify as "Open Source" under  one of the following terms:
 *   
 *    Redistributions are made at no charge beyond the reasonable cost of
 *    materials and delivery.
 *
 *    Redistributions are accompanied by a copy of the Source Code or by an
 *    irrevocable offer to provide a copy of the Source Code for up to three
 *    years at the cost of materials and delivery.  Such redistributions
 *    must allow further use, modification, and redistribution of the Source
 *    Code under substantially the same terms as this license.
 *
 * Redistributions of source code must retain the copyright notices as they
 * appear in each source code file, these license terms, and the
 * disclaimer/limitation of liability set forth as paragraph 6 below.
 *
 * Redistributions in binary form must reproduce this Copyright Notice,
 * these license terms, and the disclaimer/limitation of liability set
 * forth as paragraph 6 below, in the documentation and/or other materials
 * provided with the distribution.
 *
 * The Software is provided on an "AS IS" basis.  No warranty is
 * provided that the Software is free of defects, or fit for a
 * particular purpose.  
 *
 * Limitation of Liability. Quadcap Software shall not be liable
 * for any damages suffered by the Licensee or any third party resulting
 * from use of the Software.
 */

import java.io.*;

import com.quadcap.util.Debug;
import com.quadcap.util.Util;

/**
 * A filter output stream that tees off its output to a log file
 *
 * @author Stan Bailes
 */

public class LogOutputStream extends OutputStream {
    OutputStream        out;
    OutputStream        log;
    byte[]              prefix;
    boolean             bol = true;

    /**
     * Construct a new log output stream
     *
     * @param os the underlying output stream
     * @param log the log stream
     * @param prefix a string identifying this log stream to be prefixed
     *          to every line output by this filter.
     */
    public LogOutputStream(OutputStream os, OutputStream log, String prefix) {
        this.out = os;
        this.log = log;
        this.prefix = prefix.getBytes();
    }

    /**
     * Write a byte.
     *
     * @param b the byte.
     * @exception IOException may be thrown.
     */
    synchronized public void write(int b) throws IOException {
        out.write(b);
        if (bol) log.write(prefix);
        log.write(b);
        bol = (b == '\n');
    }

    /**
     * Write a buffer
     *
     * @param b the buffer
     * @param off the index of the first byte in the buffer to write.
     * @param len the number of bytes to write.
     *
     * @exception IOException may be thrown.
     */
    synchronized public void write(byte[] b, int off, int len)
        throws IOException
    {
        for (int i = 0; i < len; i++) write(b[off+i]);
    }

    /**
     * Write a buffer
     *
     * @param b the buffer
     *
     * @exception IOException may be thrown.
     */
    synchronized public void write(byte[] b) throws IOException {
        write(b, 0, b.length);
    }

    /**
     * Close the underlying stream and the log output stream
     *
     * @exception IOException may be thrown
     */
    public void close() throws IOException {
        out.close();
        log.close();
    }

    /**
     * Flush the underlying stream.
     *
     * @exception IOException may be thrown
     */
    public void flush() throws IOException {
        out.flush();
    }
}