Struts 2.0 is an adoption of WebWork framework from OpenSymphony and has been around for a long time now. The new framework is flexible and includes built in feature like interceptor, pojo based action classes. Moreover the action classes are not tied down to the HttpRequest & HttpResponse cycles. It also supports features like Ioc using pluggable frameworks like Spring, Guice, Plexus. There is a built in Ajax support using Dojo. On the negative side the documentation is poorly organized and getting help on advanced features of the OGNL language is diffcult.
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link: http://aspose.com