@Override
  public void addDirtyRegion(Applet applet, int x, int y, int w, int h) {
    checkThreadViolations(applet);
    super.addDirtyRegion(applet, x, y, w, h);
  }
@Override
  public void addDirtyRegion(Applet applet, int x, int y, int w, int h)