code: public static void reinitializeCurrencySettings ()
    {
      s_aRWLock.writeLocked ( () -> {
        s_aSettingsMap.clear ();
        for (final ECurrency e : ECurrency.values ())
        {
          s_aSettingsMap.put (e, new PerCurrencySettings (e));
  
          for (final Locale aLocale : e.matchingLocales ())
            if (!localeSupportsCurrencyRetrieval (aLocale))
              throw new IllegalArgumentException ("Passed locale " + aLocale + " does not support currency retrieval!");
        }
      });
    }
docs: Reinitialize all the {@link PerCurrencySettings} to the original state.