Maximum and Minimum

Moneta provides maximum and minimum reductions. Given a stream of monetary values, you could easily get the maximum or minimum values. Here's an example.

public class ReduceMaxMinMonetaryAmount {

    public static void main(String[] args) {
        CurrencyUnit dollar = Monetary.getCurrency("USD");


        MonetaryAmount money = Money.of(10, dollar);
        MonetaryAmount money2 = Money.of(10, dollar);
        MonetaryAmount money3 = Money.of(10, dollar);
        MonetaryAmount money4 = Money.of(9, dollar);
        MonetaryAmount money5 = Money.of(8, dollar);

        Optional<MonetaryAmount> max = Stream.of(money, money2, money3, money4, money5).reduce(
                MonetaryFunctions.max());//javax.money.MonetaryException: Currency mismatch: BRL/USD
        max.ifPresent(System.out::println);//USD 10

        Optional<MonetaryAmount> min = Stream.of(money, money2, money3, money4, money5).reduce(
                MonetaryFunctions.min());
        min.ifPresent(System.out::println);//USD 8

    }
}

An exception will be thrown if a currency mismatch occurs. To avoid that, an ExchangeRateProvider must be provided as shown below.

public class ReduceMaxMinMonetaryAmountExchange {

    public static void main(String[] args) {
        CurrencyUnit dollar = Monetary.getCurrency("USD");
        CurrencyUnit euro = Monetary.getCurrency("EUR");
        ExchangeRateProvider provider = MonetaryConversions.getExchangeRateProvider(ExchangeRateType.IMF);

        MonetaryAmount money = Money.of(10, dollar);
        MonetaryAmount money2 = Money.of(10, euro);
        MonetaryAmount money3 = Money.of(10, dollar);
        MonetaryAmount money4 = Money.of(9, euro);
        MonetaryAmount money5 = Money.of(8, dollar);

        Optional<MonetaryAmount> max = Stream.of(money, money2, money3, money4, money5).reduce(
                MonetaryFunctions.max(provider));//javax.money.MonetaryException: Currency mismatch: BRL/USD
        max.ifPresent(System.out::println);//EUR 10

        Optional<MonetaryAmount> min = Stream.of(money, money2, money3, money4, money5).reduce(
                MonetaryFunctions.min(provider));
        min.ifPresent(System.out::println);//USD 8

    }
}