Quadcap Embeddable Server

com/quadcap/net/server/WorkerOutputStream.java

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package com.quadcap.net.server;

/* Copyright 1999 - 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.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;

import com.quadcap.util.Debug;

/**
 * An efficient worker output stream, which is <B>NOT</B> destroyed after
 * each session, to reduce allocation overhead.  This class performs
 * all necessary buffering of the Socket OutputStream, so no extra
 * "buffer stream" classes are needed.
 *
 * @author Stan Bailes
 */
public final class WorkerOutputStream extends OutputStream {
    static final int            MAX     = 4096;
    byte[]                      buf     = new byte[MAX];
    byte[]                      temp    = new byte[16];
    int                         pos     = 0;
    OutputStream                out;

    //#ifdef DEBUG
    static boolean              doTrace = false;
    FileOutputStream            log;
    //#endif
        
    public WorkerOutputStream(FileOutputStream log) {
        //#ifdef DEBUG
        doTrace = (log != null);
        this.log = log;
        //#endif
    }

    public final void reset(OutputStream out) throws IOException {
        this.out = out;
        this.pos = 0;
        //#ifdef DEBUG
        if (doTrace) {
            log.write(("RESET " + Thread.currentThread().getName() +
                       "\r\n").getBytes());
        }
        //#endif
    }

    public final void write(int c) throws IOException {
        if (pos >= MAX) {
            owrite(buf, 0, MAX);
        }            
        buf[pos++] = (byte)c;
    }

    final void owrite(byte[] b, int off, int len) throws IOException {
        out.write(b, off, len);
        pos = 0;
        //#ifdef DEBUG
        if (doTrace) {
            log.write("WRITE\r\n".getBytes());
            log.write(b, off, len);
        }
        //#endif
    }

    public final void write(String s) throws IOException {
        int len = s.length();
        int off = 0;
        while (len + pos >= MAX) {
            int slen = MAX - pos;
            s.getBytes(off, off + slen, buf, pos);
            owrite(buf, 0, MAX);
            off += slen;
            len -= slen;
            pos = 0;
        }
        if (len > 0) {
            s.getBytes(off, len, buf, pos);
            pos += len;
        }
    }            
    
    public final void write(byte[] b, int off, int len) throws IOException {
        final int npos = pos + len;
        if (npos >= MAX) {
            if (pos == 0) {
                owrite(b, off, len);
            } else {
                final int slen = MAX - pos;
                System.arraycopy(b, off, buf, pos, slen);
                owrite(buf, 0, MAX);
                len -= slen;
                if (len < MAX) {
                    System.arraycopy(b, off + slen, buf, 0, len);
                    pos = len;
                } else {
                    pos = 0;
                    owrite(b, off + slen, len);
                }
            }
        } else {
            System.arraycopy(b, off, buf, pos, len);
            pos = npos;
        }
    }

    public final void write(byte[] b) throws IOException {
        write(b, 0, b.length);
    }

    public final void flush() throws IOException {
        if (pos > 0) {
            owrite(buf, 0, pos);
            pos = 0;
        }
        out.flush();
    }

    static final byte[] digits = "0123456789".getBytes();

    public final void writeInt(int x) throws IOException {
        int p = 0;
        while (x > 0) {
            temp[p++] = digits[x % 10];
            x /= 10;
        }
        if (p == 0) temp[p++] = (byte)'0';
        if (pos + p < MAX) {
            while (p > 0) buf[pos++] = temp[--p];
        } else {
            while (p > 0) write(temp[--p]);
        }
    }

    public final void close() throws IOException {
        flush();
        out.close();
        //#ifdef DEBUG
        if (doTrace) log.write("CLOSE\r\n".getBytes());
        //#endif
    }
}