This week's book giveaways are in the Refactoring and Agile forums. We're giving away four copies each of Re-engineering Legacy Software and Docker in Action and have the authors on-line! See this thread and this one for details.
I'm not sure what you mean by "types" of action. Do you mean subclasses like DispatchAction? I guess that the analogous thing in Struts 2 would be subclasses of ActionSupport, but you have to understand that Struts 2 actions can be Plain Old Java Beans as opposed to Struts 1, which requires an action to extend the Action class.