public void testCloning() {
        CombinedRangeXYPlot plot1 = createPlot();        
        CombinedRangeXYPlot plot2 = null;
        try {
            plot2 = (CombinedRangeXYPlot) plot1.clone();
        }
        catch (CloneNotSupportedException e) {
            e.printStackTrace();
        }
        assertTrue(plot1 != plot2);
        assertTrue(plot1.getClass() == plot2.getClass());
        assertTrue(plot1.equals(plot2));