I’ve been using Darron Schall’s xmi2as tool along with ArgoUML for a while to create UML that would eventually spit out some class structures.
Now, I know that open source will save the world and all… but I just caught on to Enterprise Architect. The newest version, the 6.0 beta (link in the top right corner of the home page), actually has round trip AS2 support built in. That means you can create UML from your classes and create classes from your UML! It’s $199 for the pro version, but I’ve never had a problem paying good money for good tools. 30 day trial free.
ActionScript is growing up!