Grails, a dynamic web-application framework based on Java and Groovy, received major new features in its recent 0.6 release. The most notable new capability is integration with Spring Web Flow, providing support for workflows and flow-managed persistence. A feature of Grails 0.6 is a flow-oriented DSL, an example of which is included in the release documentation:

class BookController {
   ...
   def shoppingCartFlow = {
       showCart {
           on("checkout").to "enterPersonalDetails"
           on("continueShopping").to "displayCatalogue"
       }
       ...
       displayCatalogue {
            redirect(controller:"catalogue", action:"show")
       }
       displayInvoice()
   }
}

Integration with Spring Web Flow also provides support for atomic conversations:

Grails integrates Hibernate with Web Flow to allow a single session to be bound for the scope of the conversation thus allowing transactional conversations with support for optimistic locking...

Grails services now support Spring scopes including integration with Web Flow scopes. Web Flow will completely manage the state transitions and Grails integrates Hibernate into the picture to make sure you get atomic conversations.

In addition to workflow scope, Grails also provides "prototype", "singleton", "request", "session", "flash", "flow," and "conversation" scopes as well.

Other features in Grails 0.6 includes RESTful URL support, and a configuration DSL that allows more in-depth customization.

What do you think of Grails as a Web framework?