A quickie session at Devoxx ’08 by Matthias Lübken was all about developing Rich Internet Applications (RIA) if you are a Plain Old Java Developer (POJD).  Matthias spoke of his wish to build RIAs without having to spend too much time learning new languages or technologies. He stumbled upon a route that let him leverage his existing Java skills

• On the client side, he used Google Web Toolkit (GWT) since it is a Java to JavaScript compiler.  I’ve never used it myself but have seen it in use in the latest interface to Mule Galaxy and liked what I saw.  Being more of a server-side man myself, I think I’ll take a little longer to get up to speed with this than Mathias did.
• On the server side, he used Grails since it is very similar to Java and he didn’t have to learn much.  I would have chosen Mule for server-side processing but it really does depend on your use case.

I had the occasion to speak to a Flex developer too so now I’m wondering what Mule developers use for front ends – GWT? Flex? Anything else?