If you haven't done JVM stuff before, it's probably best to start with the terribly unfashionable Java 1.6. All of the other JVM languages tend to use its libr

If you haven't done JVM stuff before, it's probably best to start with the terribly unfashionable Java 1.6. All of the other JVM languages tend to use its library to large extent and are using a VM which was developed for Java first, so it's good to be familiar with the underlying landscape before exploring the different riffs on it. After that, if you want to switch to another JVM language, do it, but you should have a much clearer reason than "I want to use an alternative JVM language". Something about that language should grab you. Personally, I think Groovy's great for perl-type work where you'd like to just clack something out in a terminal rather than starting up a new project in eclipse. Clojure is an actual LISP for real functional programming. Scala (IMO, no offense) is a pile of academic features that sound great in theory. Jruby is ruby.