code: public String toHsla() {
          float[] HSL = convertToHsl();
          return "hsl(" + Math.round(HSL[0]) + "," + Math.round(HSL[1]) + "%," + Math.round(HSL[2]) + "%," + a + ")";
      }
docs: Returns the CSS3 HSLA representation, e.g. hsl(120, 100%, 50%,
  0.5)