question: public void addLongSelectionListener ( SelectionListener listener ) { if ( listener == null ) throw new IllegalArgumentException ( ) ; if ( ! longSelectionListeners . contains ( listener ) ) longSelectionListeners . add ( listener ) ; }
target:  Adds a long selection listener. Events sent to the listener have long start and end points. The start point is formed by event.width as the most significant int and event.x as the least significant int. The end point is similarly formed by event.height and event.y A listener can obtain the long selection with this code: getLongSelection(SelectionEvent) long start = ((long)event.width) << 32 | (event.x & 0x0ffffffffL) Similarly for the end point: long end = ((long)event.height) << 32 | (event.y & 0x0ffffffffL)