public void testCloning() {
        XYItemEntity e1 = new XYItemEntity(
            new Rectangle2D.Double(1.0, 2.0, 3.0, 4.0),
            new TimeSeriesCollection(), 1, 9, "ToolTip", "URL"
        ); 
        XYItemEntity e2 = null;
        
        try {
            e2 = (XYItemEntity) e1.clone();
        }
        catch (CloneNotSupportedException e) {
            System.err.println("Failed to clone.");
        }
        assertTrue(e1 != e2);
        assertTrue(e1.getClass() == e2.getClass());
        assertTrue(e1.equals(e2));