The Seven Sins of Optional

Room 3 (Sabre)

It’s been three years since (among lambdas and streams) we’ve been using Optional in Java ‒ the monadic construct which makes our code much more pleasant (who likes nulls anyway?). Or does it?

This quickie will be all about Optional ‒ tiny JDK8 addition which caused a big fuzz in the community, even before it was released. I’ll try to point both good and bad Optional usages (especially the bad ones) and also mention very handy additions in upcoming JDK9.