The following test case will generate a failure despite all values being in range. The problem is that sometimes float->double->int conversions implicit in the math of the interpolate function can generate values every so slightly out of range...

    @Test
    public void testOfTheWayAll() {
        List<Color> colors = new ArrayList<Color>();
        for (Field f : Color.class.getDeclaredFields()) {
            if (Modifier.isStatic(f.getModifiers()) &&
                f.getType() == Color.class)
            {
                try {
                    colors.add((Color) f.get(null));
                } catch (IllegalArgumentException ex) {
                } catch (IllegalAccessException ex) {
                }
            }
        }
        System.out.println("colors: "+colors.size());
        for (Color c1 : colors) {
            for (Color c2 : colors) {
                c1.interpolate(c2, 0.0);
                c1.interpolate(c2, 0.5);
                c1.interpolate(c2, 1.0);
            }
        }
    }