I have not done web development in Java for the past three years and now I need to use one for a project I am working on. I am thinking of using Seam, Flex + BlazeDS, Struts2 or Spring MVC. The most attractive of the four is Flex, however I am trying to stay away from it since the app will end up being entirely in Flash. Struts2 and Seam are mature but might require more time to learn. I had basic experience with Spring framework in the past so I am also considering its MVC.
Should I use one of these or go for some other framework?