public void testEquals() {
        StackedXYBarRenderer r1 = new StackedXYBarRenderer();
        StackedXYBarRenderer r2 = new StackedXYBarRenderer();
        assertTrue(r1.equals(r2));
        assertTrue(r2.equals(r1));

        r1.setRenderAsPercentages(true);
        assertFalse(r1.equals(r2));
        r2.setRenderAsPercentages(true);
        assertTrue(r1.equals(r2));