If you have developers that know Java and nothing else, which is not all that uncommon, it's really your only option. And since any developer who can't or won't learn additional languages is probably not very good, using a language like Java provides the fluff and bloat necessary to keep these untalented devs from screwing too many things up. Java's primary advantage in general is interchangeability of engineers.

If you have developers that know other JVM languages, or who can learn, then I would say there is no advantage because any language on the JVM can refer to object built in any other. This is why things like Jython, JRuby, Rhino, and Clojure are cool.