docs: public static String roundCorner(int radiusInner, int radiusOuter, int color) {
      if (radiusInner < 1) {
        throw new IllegalArgumentException("Radius must be greater than zero.");
      }
      if (radiusOuter < 0) {
        throw new IllegalArgumentException("Outer radius must be greater than or equal to zero.");
      }
      StringBuilder builder = new StringBuilder(FILTER_ROUND_CORNER).append("(").append(radiusInner);
      if (radiusOuter > 0) {
        builder.append("|").append(radiusOuter);
      }
      final int r = (color & 0xFF0000) >>> 16;
      final int g = (color & 0xFF00) >>> 8;
      final int b = color & 0xFF;
      return builder.append(",") //
          .append(r).append(",") //
          .append(g).append(",") //
          .append(b).append(")") //
          .toString();
    }