public void testAddListenerWithIllegalArguments() { Fixture.fakePhase(PhaseId.PROCESS_ACTION); Display display = new Display(); Widget widget = new Shell(display); IEventAdapter eventAdapter = (IEventAdapter) widget.getAdapter(IEventAdapter.class); try { eventAdapter.addListener(SelectionListener.class, new Object()); fail(); } catch (final IllegalArgumentException iae) { } try { eventAdapter.addListener(SelectionListener.class, null); fail(); } catch (final IllegalArgumentException iae) { } try { SelectionListener validListener = new SelectionAdapter() {}; eventAdapter.addListener(null, validListener); fail(); } catch (final IllegalArgumentException iae) { } Object[] listeners = eventAdapter.getListener(SelectionListener.class); assertEquals(0, listeners.length); }