Vaadin with Seam

General
1

Hello everybody,

First at all; I would like to congratulate all the team for their great job on Vaadin. I’am really impressed.

The thing is that I have to use Seam/JSF and Vaadin in the same application.

I have a already big application working with MySQL/Hibernates/Seam/JSF-RichFaces.
I would like to propose to my client a more user-friendly interface and with modern browser I think that RIA have good futur. For that, I want to use Vaadin.

I made a few design study. I want to keep the database / hibernates entities.
I will redo a new business layer (for complex treatment) working for Seam/JSF backbean

My problems are :

  • How to manage with Hibernate Session. What the best way ? Invoking a seam component and get entityManager by injection or going with classic hibernate session ?
  • What about Lazy loading ?
  • How to link authentication with Seam JAAS

Does anyone have already done this ?
Any advice ?

Regards,
Fred

2

Hi !
We have seam (jpa + richfaces) application and we want to redesign some forms using vaadin to make them more usable.
So i started to try to use seam contexts and components with vaadin application.
Here is my experience (experimental):
Vaadin and seam works fine together (for seam vaadin is just another user’s servlet)
but:

  1. add vaadin servlet path (used in web.xml) to seam filter mapping

  2. we need to manage transactions:
    // in Application init code
    getContext().addTransactionListener(new SeamTransactionListener());
    and SeamTransactionListener is (based on seam code):

public class SeamTransactionListener implements TransactionListener {

	private static final long serialVersionUID = 1L;

	public void transactionEnd(Application application, Object transactionData) {
		// will unlock the conversation if any locked
		Manager.instance().unlockConversation();
		System.out.println("Transaction end");

		if (Init.instance().isTransactionManagementEnabled())
			commitOrRollback(); // we commit before destroying contexts, cos the
	}

	public void transactionStart(Application application, Object transactionData) {
		// TODO Auto-generated method stub
		System.out.println("Transaction start");
		if (Init.instance().isTransactionManagementEnabled())
			begin();
		if (application instanceof VApp) 
			((VApp) application).nextTransaction();
	}

	private void commitOrRollback() {
		try {
			if (Transaction.instance().isActive()) {
				try {
					Transaction.instance().commit();
				} catch (IllegalStateException e) {
					System.err
							.println("TX commit failed with illegal state exception. This may be "
									+ "because the tx timed out and was rolled back in the background.");
				}
			} else if (Transaction.instance().isRolledBackOrMarkedRollback()) {
				Transaction.instance().rollback();
			}

		} catch (Exception e) {
			throw new IllegalStateException("Could not commit transaction", e);
		}
	}

	private void begin() {
		try {
			if (!Transaction.instance().isActiveOrMarkedRollback()) {
				// log.debug("beginning transaction ");
				Transaction.instance().begin();
			}
		} catch (Exception e) {
			throw new IllegalStateException("Could not start transaction", e);
		}
	}

}

We use seam’s conversations, so when i need to use some conversation-scope components from vaadin event listeners, i call this method to “attach” to some conversation:

public static void restoreConversation(String cid) {
			System.out.println("Restoring conversation " + cid);
			System.out.println("Existsing conversations : "
					+ ConversationEntries.instance().getConversationIds());
			
			if (Conversation.instance().isLongRunning() ) {
				if (Conversation.instance().getId().equals(cid)) {
					System.out.println("already here : " + cid);
					return;
				} else 
					Manager.instance().unlockConversation();
			}
			

			Map<String, Object> params = new HashMap<String, Object>();
			params.put(Manager.instance().getConversationIdParameter(), cid);
			ConversationPropagation.instance().restoreConversationId(params);
			Manager.instance().restoreConversation();
}

So all seam features (entityManager, identity, etc) works fine.
For example, user can login using vaadin form -

...
        private TextField userName;
	private TextField pwd;
.....
 Button b = new Button("Login");
        b.addListener(new Button.ClickListener() {
			
			public void buttonClick(ClickEvent event) {
				login();
			}
		});
....

protected void login() {
		Identity identity = Identity.instance();
		identity.setUsername(userName.getValue().toString());
		identity.setPassword(pwd.getValue().toString());
		
		identity.login();
		
		if (identity.isLoggedIn()) {
			getWindow().showNotification("Welcome, " + identity.getCredentials().getUsername());
			// do some user-specific sfuff here (load menu, show main form, etc)
		} else {
			getWindow().showNotification("Oops !",  Notification.TYPE_ERROR_MESSAGE);
		}
		
	}
...
3

Hi Maxim !

I’m triying to do the same thing with your code: integrate vaadin to a seam application but it’s not working for me…

Could you please provide some more details ?

Your web.xml file content for example or any other helping source…

Thanks

Salvo

4

This solution is also valid with SEAM 3.0.0 ???

Thank you

5

Please everybody…I really need your help !!! :frowning: