[twic]

Spring (Boot) is the biggest.

After that, in terms of being standard and widely-used, Java EE, now known as Jakarta EE. It has a comparable level of magic to Spring Boot; maybe some of it is done better, some of it isn't.

DropWizard is still going.

I suspect that a larger proportion of Java programmers are working on headless data-munging backend apps than, say, Ruby or Node programmers. Those kinds of apps often either don't need a framework at all, or need some more specialist framework. Hence, Rails-esque frameworks are less of a priority for the Java community as a whole. Which is a bit of a shame, because it would be great to have a really strong alternative to Spring.