code: public static String toColorWithAlpha(String red, String green, String blue) {
  		String defaultAlpha = "FF";
  		if (red != null && !red.isEmpty()
  				&& Character.isLowerCase(red.charAt(0))) {
  			defaultAlpha = defaultAlpha.toLowerCase();
  		}
  		return toColorWithAlpha(red, green, blue, defaultAlpha);
  	}
docs: Convert the hex color values to a hex color including an opaque alpha
  value of FF
  
  @param red
  red hex color in format RR or R
  @param green
  green hex color in format GG or G
  @param blue
  blue hex color in format BB or B
  
  @return hex color in format #AARRGGBB