code: public static boolean isValidVATIN (@Nonnull final String sVATIN, final boolean bIfNoValidator)
    {
      ValueEnforcer.notNull (sVATIN, "VATIN");
      if (sVATIN.length () > 2)
      {
        final String sCountryCode = sVATIN.substring (0, 2).toUpperCase (Locale.US);
        final IToBooleanFunction <String> aValidator = s_aMap.get (sCountryCode);
        if (aValidator != null)
          return aValidator.applyAsBoolean (sVATIN.substring (2));
      }
  
      // No validator
      return bIfNoValidator;
    }
docs: Check if the provided VATIN is valid. This method handles VATINs for all
  countries. This check uses only the checksum algorithm and does not call
  any webservice etc.
  
  @param sVATIN
  VATIN to check. May not be <code>null</code>.
  @param bIfNoValidator
  What to return if no validator was found?
  @return <code>true</code> if the VATIN is valid (or unknown).
  @since 6.0.1