Chaining Optionals in Java 8

Question

Looking for a way to chain optionals so that the first one that is present is returned. If none are present Optional.empty() should be returned.

Assumi

Answer 1

Use a Stream:

Stream.of(find1(), find2(), find3())
    .filter(Optional::isPresent)
    .map(Optional::get)
    .findFirst();

If you need to evaluate the find methods lazily, use supplier functions:

Stream.of(this::find1, this::find2, this::find3)
    .map(Supplier::get)
    .filter(Optional::isPresent)
    .map(Optional::get)
    .findFirst();