When comparing Java vs Actix, the Slant community recommends Actix for most people. In the question“What are the best backend web frameworks?” Actix is ranked 22nd while Java is ranked 42nd.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Verbosity
It makes it easy to debug and to read code.
Pro Mature ecosystem
The language and all its tools have enough time to age and they've aged well.
Pro Type-safe
It is easier to catch errors sooner.
Pro Blazingly fast
Pro Feature-rich
Actix provides a lot of features out of box. WebSockets, HTTP/2, pipelining etc
Pro Type-safe
Forget about stringly typed objects, from request to response, everything has types
Pro Extensible
Easily create your own libraries that any Actix application can use
Cons
Con Memory hungry
Running the virtual machine, application server and application itself consumes significant amount of resources.
Con Unnecessarily obtuse and verbose
If you like typing 40 lines of code to open a file, Java is the language for you. If, on the other hand, you’d actually like to get something done, look elsewhere.
Con Oracle
Enough said.
In more detail: Oracle has acquired Java from Sun and continues to surround it with controversy ever since (legendary lawsuit with google, money extortion from the enterprise users etc.).