web services and transactions

Hello,

Question 1:
I have an EJB web service. If the web service is invoked from another EJB which is in the middle of a transaction, and the web service has the transaction attribute set to: TransactionAttributeType.REQUIRED, will a new transaction be created in the web service, or will the caller's transaction be used?

Question 2:
I have a servlet based web service which invokes a stateless session bean with TransactionAttributeType.REQUIRED set. If another EJB that is currently in a transaction invokes the servlet based web service, will the stateless session bean invoked by the web service always create a new transaction?

Thanks so much.

Ravi

Why do you think an SLSB exposed as a web service cannot support "mandatory"?

Because the transaction does not propagate over the HTTP/SOAP link.

"required" will always start a new transaction.

An SLSB being accessed as a web service is being accessed as a web service - not as an SLSB

An EJB client accessing a web service has no idea whether the web service is actually based on a SLSB - so EJB features don't apply.

See also Servlet endpoint Vs EJB endpoint

Now if both ends have Project Tango installed then WS-AtomicTransaction is used to propagate transactions over the web service link. But that is a very special case...

Peer,

I am deploying my web service on Glassfish which I believe has Tango. Will I have to configure it to get the behavior you mentioned? I am so glad for your response.

Many Thanks.

Ravi

I'm not sure but I wouldn't be surprised if it is automatically active as part of WSIT on Glassfish. Something about WS-AtomicTransaction automatically working for SLSBs and that it can be used manually on servlets.

About the basicWSTX Example

So Glassfish-to-Glassfish and Glassfish-to-Microsoft WCF should work. But I haven't come across any evidence that either WS-AtomicTransaction or WSIT are part of Java EE 5. Though JBoss 5 seems to include WS-AtomicTransaction support.
But it is probably safer to look at this as WS-AtomicTransaction support - not EJB transaction support - it would be surprising if things lined up perfectly.

Thanks, Peer. I wouldn't be aware of this without your help. There may be cases where we want the web service to be part of its caller's transaction. This is very helpful.

Many thanks.

Ravi