Beating a dead horse here - but Streams and Generics are now what I personally consider vital features. Code is much more compact and elegant with the proper application of these two features.

Error handling via exceptions and generics are things that I can't live without. Go moves in that direction, as far as I understand, generics are expected in the next versions of Go and error handling somewhat improved, so may be it'll be good enough after few years, but I just can't write current Go after Java, it's like running with chained legs.

Other than what the other posters mentioned, you have things like annotations in Java that allow for cool features such as validation and constraints, and auto translation between types. This is extremely verbose and error prone in golang because no such mechanism exists.

Vital features is double speak for any Java feature that isn’t in Go.