code: public static boolean isSpecialLocaleCode (@Nullable final String sLocale)
    {
      return LOCALE_ALL_STR.equalsIgnoreCase (sLocale) || LOCALE_INDEPENDENT_STR.equalsIgnoreCase (sLocale);
    }
docs: Check if the passed locale is one of the special locales "all" or
  "independent"
  
  @param sLocale
  The locale to check. May be <code>null</code>.
  @return if the passed locale is not <code>null</code> and a special locale.
  @see #LOCALE_ALL
  @see #LOCALE_INDEPENDENT