Whats the most elegant way to add two numbers that are Optional

Question

I need to perform an add operation on two big decimals that are wrapped optionals:

Optional ordersTotal;
Optional newOrder;
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Answer 1

Not sure if you'll consider it more elegant, but here's one alternative:

ordersTotal = Optional.of(ordersTotal.orElse(BigDecimal.ZERO).add(newOrder.orElse(BigDecimal.ZERO)));

Another, based on @user140547's suggestion:

ordersTotal = Stream.of(ordersTotal, newOrder)
        .filter(Optional::isPresent)
        .map(Optional::get)
        .reduce(BigDecimal::add);

Note that the first version returns Optional.of(BigDecimal.ZERO) even when both optionals are empty, whereas the second will return Optional.empty() in such a case.