Introduce a validation library like jetbrains.annotations

[ursjoss]

It would be very helpful if we can use some annotation based approach to hint to the compiler about nullability of variables/parameters. See here for an overview on such frameworks.

Personally, I like the ones from org.jetbrains.annotation (see e.g. here), but I don't have a strong oppinion.

[RadekCap]

Personally, I like the ones from org.jetbrains.annotation (see e.g. here), but I don't have a strong oppinion.

I remember nothing more about this library than I liked usage of it. :)

In this light it seems like a good idea to me.