code: private static int utf8Length(String string) {
      int stringLength = string.length();
      int utf8Length = 0;
      for (int i = 0; i < stringLength; i++) {
        int c = string.charAt(i);
        if (c <= 0x007F) {
          utf8Length++;
        } else if (c > 0x07FF) {
          utf8Length += 3;
        } else {
          utf8Length += 2;
        }
      }
      return utf8Length;
    }
docs: Returns the number of bytes required to write this.