void () { 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 } } } }