code: public static Predicate<MonetaryAmount> isCurrency(
  			CurrencyUnit... currencies) {
  
  		if (Objects.isNull(currencies) || currencies.length == 0) {
  			return m -> true;
  		}
  		Predicate<MonetaryAmount> predicate = null;
  
  		for (CurrencyUnit currencyUnit : currencies) {
  			if (Objects.isNull(predicate)) {
  				predicate = m -> m.getCurrency().equals(currencyUnit);
  			} else {
  				predicate = predicate.or(m -> m.getCurrency().equals(
  						currencyUnit));
  			}
  		}
  		return predicate;
      }
docs: Create predicate that filters by CurrencyUnit.
  @param currencies
  the target {@link javax.money.CurrencyUnit}
  @return the predicate from CurrencyUnit