I think the premise of JEE is that you label your class by @SessionBean annotation, and everything is installed automatically for that class: RPC, load balancing, security, monitoring, and you don't need to shop for individual components and find the way how to glue them together. How this premise is implemented is another story. I am not sure about quality because didn't use jee for last 10 years, but when I was using it, IBM stack was far ahead of everything on the market, and was like your private PaaS with cloud functions, but with high license fees of course.