assertEquals(Color.black, s.getPaint(-1.0));
        assertEquals(Color.black, s.getPaint(0.0));
        assertEquals(Color.blue, s.getPaint(50.0));
        assertEquals(Color.blue, s.getPaint(100.0));
        assertEquals(Color.black, s.getPaint(101.0));
        
        s.add(new Double(50.0), Color.red);