content: /*
   * Copyright (c) 2001-2004 Caucho Technology, Inc.  All rights reserved.
   *
   * The Apache Software License, Version 1.1
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. The end-user documentation included with the redistribution, if
   *    any, must include the following acknowlegement:
   *       "This product includes software developed by the
   *        Caucho Technology (http://www.caucho.com/)."
   *    Alternately, this acknowlegement may appear in the software itself,
   *    if and wherever such third-party acknowlegements normally appear.
   *
   * 4. The names "Hessian", "Resin", and "Caucho" must not be used to
   *    endorse or promote products derived from this software without prior
   *    written permission. For written permission, please contact
   *    info@caucho.com.
   *
   * 5. Products derived from this software may not be called "Resin"
   *    nor may "Resin" appear in their names without prior written
   *    permission of Caucho Technology.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL CAUCHO TECHNOLOGY OR ITS CONTRIBUTORS
   * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
   * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
   * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
   * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
   * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
   * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   *
   * @author Scott Ferguson
   */
  
  package com.caucho.hessian.mux;
  
  import java.io.IOException;
  import java.io.OutputStream;
  
  /**
   * Output stream to a specific channel.
   */
  public class MuxOutputStream extends OutputStream {
    private MuxServer server;
    private int channel;
    private OutputStream os;
  
    /**
     * Null argument constructor.
     */
    public MuxOutputStream()
    {
    }
  
    /**
     * Initialize the multiplexor with input and output streams.
     */
    protected void init(MuxServer server, int channel)
      throws IOException
    {
      this.server = server;
      this.channel = channel;
      this.os = null;
    }
  
    /**
     * Gets the raw output stream.  Clients will normally not call
     * this.
     */
    protected OutputStream getOutputStream()
      throws IOException
    {
      if (os == null && server != null)
        os = server.writeChannel(channel);
      
      return os;
    }
  
    /**
     * Gets the channel of the connection.
     */
    public int getChannel()
    {
      return channel;
    }
  
    /**
     * Writes a URL to the stream.
     */
    public void writeURL(String url)
      throws IOException
    {
      writeUTF('U', url);
    }
    
    /**
     * Writes a data byte to the output stream.
     */
    public void write(int ch)
      throws IOException
    {
      OutputStream os = getOutputStream();
      
      os.write('D');
      os.write(0);
      os.write(1);
      os.write(ch);
    }
  
    /**
     * Writes data to the output stream.
     */
    public void write(byte []buffer, int offset, int length)
      throws IOException
    {
      OutputStream os = getOutputStream();
      
      for (; length > 0x8000; length -= 0x8000) {
        os.write('D');
        os.write(0x80);
        os.write(0x00);
        os.write(buffer, offset, 0x8000);
        
        offset += 0x8000;
      }
  
      os.write('D');
      os.write(length >> 8);
      os.write(length);
      os.write(buffer, offset, length);
    }
  
    /**
     * Flush data to the output stream.
     */
    public void yield()
      throws IOException
    {
      OutputStream os = this.os;
      this.os = null;
  
      if (os != null)
        server.yield(channel);
    }
  
    /**
     * Flush data to the output stream.
     */
    public void flush()
      throws IOException
    {
      OutputStream os = this.os;
      this.os = null;
  
      if (os != null)
        server.flush(channel);
    }
  
    /**
     * Complete writing to the stream, closing the channel.
     */
    public void close()
      throws IOException
    {
      if (server != null) {
        OutputStream os = getOutputStream();
        this.os = null;
        
        MuxServer server = this.server;
        this.server = null;
  
        server.close(channel);
      }
    }
  
    /**
     * Writes a UTF-8 string.
     *
     * @param code the HMUX code identifying the string
     * @param string the string to write
     */
    protected void writeUTF(int code, String string)
      throws IOException
    {
      OutputStream os = getOutputStream();
      
      os.write(code);
      
      int charLength = string.length();
  
      int length = 0;
      for (int i = 0; i < charLength; i++) {
        char ch = string.charAt(i);
  
        if (ch < 0x80)
          length++;
        else if (ch < 0x800)
          length += 2;
        else
          length += 3;
      }
      
      os.write(length >> 8);
      os.write(length);
      
      for (int i = 0; i < length; i++) {
        char ch = string.charAt(i);
  
        if (ch < 0x80)
          os.write(ch);
        else if (ch < 0x800) {
          os.write(0xc0 + (ch >> 6) & 0x1f);
          os.write(0x80 + (ch & 0x3f));
        }
        else {
          os.write(0xe0 + (ch >> 12) & 0xf);
          os.write(0x80 + ((ch >> 6) & 0x3f));
          os.write(0x80 + (ch & 0x3f));
        }
      }
    }
  }
  