[civopsec]

The type system isn’t impressive. You can find usages and thereby get navigation and refactoring via excellent Java-centric IDEs. But it seems like that’s it(?). On the other hand you have to constantly exercise your code because of lurking NPEs. Although hopefully we can get good annotations through third-party tooling (Facebook’s looks good).

[EdwardDiego]

I do like Kotlin's nullable types for that reason alone. At least Java has far better NPE messages now.

https://www.baeldung.com/java-14-nullpointerexception

[emodendroket]

That's a lot on its own, and being able to understand the argument and return types solely by signature is a big productivity boost compared to environments where that isn't possible.