[AtlasBarfed]

IMO:

IntelliJ for IDE (Community edition is free). #1 reason is it supports Kotlin and Groovy very well out of the box. Eclipse is still a plugin disaster, and the language support aside from Java is pretty bad, although I haven't bothered to check in a few years since IntelliJ CE was released.

Gradle for builds. It is still copy and paste setup, but at least you can do a lot more things than rigid Maven.

Groovy + CompileStatic (personally) for the actual JVM language but admittedly I haven't tried Kotlin yet. Even with closures and other improvements, base Java can't compete with either of those.

Spring Boot for your enterprisey stuff/REST services which you are likely using it for. It's such a standard at this point.

Unit tests: Spock. Spock is awesome. And very well supported by IntelliJ for autoformat, another BIG reason to use IntelliJ.

Man, web frameworks on Java that don't just use it for an AJAX service layer? Who knows.