logger.debug("Writing " + bufferCount + " bytes.");
  public void flush() throws IOException  {    if (bufferCount == 0) return;    if (multiplex)      {        logger.debug("Writing " + bufferCount + " bytes.");        write(FNONE, outputBuffer, 0, bufferCount);      }    else      {        out.write(outputBuffer, 0, bufferCount);      }    bufferCount = 0;  }