assertTrue("Expected exception not thrown", exceptionThrown);
public void test_addSelectionListenerLorg_eclipse_swt_events_SelectionListener() {	listenerCalled = false;	boolean exceptionThrown = false;	SelectionListener listener = new SelectionListener() {		public void widgetSelected(SelectionEvent event) {			listenerCalled = true;		}		public void widgetDefaultSelected(SelectionEvent event) {		}	};	try {		combo.addSelectionListener(null);	}	catch (IllegalArgumentException e) {		exceptionThrown = true;	}	combo.addSelectionListener(listener);	combo.select(0);	assertTrue(":a:", listenerCalled == false);	combo.removeSelectionListener(listener);	try {		combo.removeSelectionListener(null);	}	catch (IllegalArgumentException e) {		exceptionThrown = true;	}}