Separation of User Interface from Business Layer with Seam

[rconaway]

Most of the write-ups about Seam emphasize how much it helps integrate the user interface (JSF) with the persistence layer.

But what about a layered architecture where we don't want them together? I'm working on a project where JSF will be used to rewrite and extend the user interface of an existing application. In many cases, business logic is already embedded in a business layer that will be reused. We intend to maintain this separation of concerns, keeping business logic away from the UI.

The UI will never talk to the persistence layer, only the the business layer. How does Seam fit into this kind of a model? Given that we want to use dependency injection in the business layer, does it make sense to use Seam or is something like Spring sufficient?

Thank you in advance for any advice.

Rob

[wise_guybg]

I guess Guice is also an option:
http://code.google.com/p/google-guice/

My opinion is that Seam is a bit heavy for your needs. It depends though...

[michael.c.small]

Seam allows you structure your application in any number of ways. There is nothing preventing you from calling your business tier objects from your Seam components (e.g. inject your business tier services through @EJB). Then your Seam components call the business tier objects to perform the business logic and persistence. Think of Seam not as UI and persistence framework, but as an application framework that sits on top of your business tier.