Thiago Alves de Moraes

Remote method should have arguments and return types serializable because you are going through a remote call, that is, passing data through the network.

Are you using Session replication with a shared database ?

take a look at this link
tomcat clustering - how to

I think you cannot do what you want.

Hi!

Take a look at http://download.oracle.com/javaee/5/api/javax/persistence/EntityManager.html

EntityManager is an interface with methods for interacting with the persistence context, such as persist, update, delete and so on...

Good definition here http://docs.jboss.org/hibernate/entitymanager/3.5/reference/en/html/architecture.html

The @PersistenceContext is the anotation for the injection of the current persistence context

Yes. You can use the synchronizer token (JEE Pattern).
Using this pattern you address the double submit problem in your application.

I don't think JSF has this feature out of the box.

Take a look at the code inside initialize method
EmailValidator validator = EmailValidator.getInsance();

validator is an reference inside the scope of the method.

you should create a new property of the class
EmailValidator validator ; private void initialize() { validator = EmailValidator.getInsance(); }

And then it works

JSF is probably slower than the others.

JSF has phases and one of them restores the whole component tree in the server side.

This might be an issue if your app has performance requirements.

Hi Aryan,

You should use the optmistic or pessimistic locks for hadling concurrent access.

Take a look at those locks and choose the best solution for your system!

Hi Nirvan!
Once the user (web tier) has been authenticated via JAAS, the client can call ejbs securely. The authentication is propagated to the ejb upon method invocation.

You should supply different configurations for the web and EJB tiers.

In the web.xml you specify the the authentication method and security constraints for your pages.

In the EJB deployment descriptor (or annotations ) you specify the security roles allowed for method invocations.

They share the same authentication but the configuration is different.