protected void disposeDrawingBuffer(){
  Image localDrawingBuffer=drawingBuffer;
  drawingBuffer=null;
  if (localDrawingBuffer != null) {
    localDrawingBuffer.flush();
  }
}

protected void disposeDrawingBuffer ( ) { Image localDrawingBuffer = drawingBuffer ; drawingBuffer = null ; if ( localDrawingBuffer != null ) { localDrawingBuffer . flush ( ) ; } }
clear out resources for the current drawing buffer .
