code: public final String getShortCodeWithCountryAndVariant() {
      String name = getShortCode();
      if (getCountries().length == 1 && !name.contains("-x-")) {   // e.g. "de-DE-x-simple-language"
        name += "-" + getCountries()[0];
        if (getVariant() != null) {   // e.g. "ca-ES-valencia"
          name += "-" + getVariant();
        }
      }
      return name;
    }
docs: Get the short name of the language with country and variant (if any), if it is
  a single-country language. For generic language classes, get only a two- or
  three-character code.
  @since 3.6