code: public static String toUnicode(String s, int flags) {
      String[] parts = SEPARATORS_REGEX.split(s);
      for (int i = 0; i < parts.length; i++) {
        if (parts[i].startsWith(PUNYCODE_PREFIX)) {
          parts[i] = decode(parts[i].substring(PUNYCODE_PREFIX.length()));
        }
      }
      return String.join(".", parts);
  
    }
docs: Convert an IDN-formatted ASCII string to Unicode.