a1.setAxisLinePaint(new GradientPaint(1.0f, 2.0f, Color.red, 
                3.0f, 4.0f, Color.black));
        assertFalse(a1.equals(a2));
        a2.setAxisLinePaint(new GradientPaint(1.0f, 2.0f, Color.red, 
                3.0f, 4.0f, Color.black));
        assertTrue(a1.equals(a2));