assertNull( designElement.listeners );
assertNull( CoreTestUtil.getListeners( designElement ) );
	public void testAddRemoveListener( ) throws Exception	{		assertNull( designElement.listeners );		MyActionListener listener = new MyActionListener( );		// Add listner		designElement.addListener( listener );		assertTrue( designElement.listeners.contains( listener ) );		// Remove listener		designElement.removeListener( listener );		assertFalse( designElement.listeners.contains( listener ) );		// Remove a non-existing listener		designElement.removeListener( listener );		assertFalse( designElement.listeners.contains( listener ) );		// remove all listeners.		designElement.clearListeners( );		listener = new MyActionListener( );		DesignElementHandle handle = designElement.getHandle( design );		handle.addListener( listener );		// add an element then undo.		designHandle.getBody( ).add( handle );		assertEquals( 1, designElement.listeners.size( ) );		designHandle.getCommandStack( ).undo( );		assertNull( designElement.listeners );		designHandle.getCommandStack( ).redo( );		assertNull( designElement.listeners );		designHandle.getCommandStack( ).undo( );		assertNull( designElement.listeners );		// drop an element, listeners are removed.		handle.addListener( listener );		designHandle.getBody( ).add( handle );		handle.dropAndClear( );		assertNull( designElement.listeners );		designHandle.getCommandStack( ).undo( );		assertNull( designElement.listeners );		designHandle.getCommandStack( ).redo( );		assertNull( designElement.listeners );	}