code: public static boolean isRoundingAvailable(CurrencyUnit currencyUnit, String... providers) {
          return Optional.ofNullable(monetaryRoundingsSingletonSpi()).orElseThrow(
                  () -> new MonetaryException("No MonetaryRoundingsSpi loaded, query functionality is not available."))
                  .isRoundingAvailable(currencyUnit, providers);
      }
docs: Checks if a {@link MonetaryRounding} is available given a roundingId.
  
  @param currencyUnit The currency, which determines the required scale. As {@link java.math.RoundingMode},
  by default, {@link java.math.RoundingMode#HALF_UP} is used.
  @param providers    the providers and ordering to be used. By default providers and ordering as defined in
  #getDefaultProviders is used.
  @return true, if a corresponding {@link javax.money.MonetaryRounding} is available.
  @throws IllegalArgumentException if no such rounding is registered using a
  {@link javax.money.spi.RoundingProviderSpi} instance.