code: public boolean isCurrencyAvailable(Locale locale, String... providers) {
          return !getCurrencies(CurrencyQueryBuilder.of().setCountries(locale).setProviderNames(providers).build()).isEmpty();
      }
docs: Allows to check if a {@link javax.money.CurrencyUnit} instance is
  defined, i.e. accessible from {@link #getCurrency(String, String...)}.
  
  @param locale    the target {@link java.util.Locale}, not {@code null}.
  @param providers the (optional) specification of providers to consider. If not set (empty) the providers
  as defined by #getDefaultRoundingProviderChain() should be used.
  @return {@code true} if {@link #getCurrencies(java.util.Locale, String...)} would return a
  non empty result for the given code.