code: public Color next() {
          int r = rand.nextInt(256);
          int g = rand.nextInt(256);
          int b = rand.nextInt(256);
          return (seed == null)
              ? new Color(r, g, b)
              : new Color((r + seed.getRed()) / 2,
                          (g + seed.getGreen()) / 2,
                          (b + seed.getBlue()) / 2);
      }
docs: Returns the next random color