public void testCloning() {
        StandardDialFrame f1 = new StandardDialFrame();
        StandardDialFrame f2 = null;
        try {
            f2 = (StandardDialFrame) f1.clone();
        }
        catch (CloneNotSupportedException e) {
            e.printStackTrace();
        }
        assertTrue(f1 != f2);
        assertTrue(f1.getClass() == f2.getClass());
        assertTrue(f1.equals(f2));
        
        // check that the listener lists are independent
        MyDialLayerChangeListener l1 = new MyDialLayerChangeListener();
        f1.addChangeListener(l1);
        assertTrue(f1.hasListener(l1));
        assertFalse(f2.hasListener(l1));