private int flush(int offset){
  try {
    _os.write(_buffer,0,offset);
    _offset=0;
    return 0;
  }
 catch (  IOException e) {
    throw new H3ExceptionOut(e);
  }
}

private int flush ( int offset ) { try { _os . write ( _buffer , 0 , offset ) ; _offset = 0 ; return 0 ; } catch ( IOException e ) { throw new H3ExceptionOut ( e ) ; } }
flush the buffer and set the offset to zero .
