I know there's a lot of debate on using stateful vs stateless EJBs in web applications.
The shopping cart is the most common use case: Oracle's Java EE examples use it a lot in the official docs, too.
Here on stackoverflow I found many interesting answers like this The Shopping Cart dilemma in JavaEE which often say something like:
ok... SFSB are good in enterprise, complex scenarios, e.g. if you want to share them with other applications and make them available not only to JSF/web clients
but... if you're just developing your grandpa's e-commerce website, just stick to the HttpSession / SessionScoped cdi-managed bean, and write your business methods in SLSB, as they are more efficient, and so on...
However, because I'm still in a learning and discovery phase, I just want to give SFSB a try, by myself, trying to build a simple shopping cart.
I saw an interesting tutorial suggesting to store a JNDI-retrieved instance of the @Stateful shopping cart ejb interface in the HttpSession, the first time the web client needed it, then use it as usual, during the web session. In my JSF presentation layer, I suppose I would have a @SessionScoped @Named bean (let's call it ShopController), and, in its initialization, store one instance of the stateful ejb in an instance variable.
I wonder if it's possible to directly bind the @Stateful bean to the http session by annotating it with the @SessionScoped CDI annotation.
Will it work as described above? Will CDI create one SFSB for each web session?
@SessionScoped is for @Named beans and @Stateful is for @EJB beans. If I'm not wrong, you cannot annotate 1 bean with both. If you want to use @Stateful, just annotate your ShoppingCart bean with @EJB and @Local and then reference it in your ShopController. Something like this:
@Named
@SessionScoped
public class ShopController {
...
@EJB
private ShoppingCart cart;
...
// Getters and Setters
}
@Local
@Stateful
public class ShoppingCart {
...
}