private void checkScrollingCapabilities() {
    if (myPreviousNotification == null || myPreviousNotification.isExpired()) {
      if (!Boolean.TRUE.equals(isWindowBlitterAvailableFor(this))) {
        myPreviousNotification = notify("Scrolling: cannot use window blitter"); //NON-NLS
      }
      else {
        if (!Boolean.TRUE.equals(isTrueDoubleBufferingAvailableFor(this))) {
          myPreviousNotification = notify("Scrolling: cannot use true double buffering"); //NON-NLS
        }
      }
    }
  }
private void checkScrollingCapabilities()