getUserTransaction method

[Muthaiah Ramanathan]

In the ejbCreate or ejbRemove method of a STATELESS SESSION bean class, can we access use the method getUserTransaction() on the session context object?

The book by Paul Sangerra says, we cannot access it and the HFEJB(in the errata page) says it can be accessed. Which is true...?

[MI Mohammed]

the getUserTransaction() can only be called from both ejbRemove() and ejbCreate() of a BMT Bean. CMT Bean can not call never getUserTransaction() from any of it's methods, says the spec.

[Aleena Rehman]

We cannot use getUserTransaction() in ejbRemove(),ejbCreate() of Stateless Session bean ....

Reason is very simple....
ejbCreate() and ejbRemove() are called by the container at a time when he feels its time to increase/reduce the pool (Not by a client invocation, and therefore this means Transaction will not be available). The methods are called in an "unspecified transaction context", and therefore this method cannot be called.

Regards,
Aleena

[Muthaiah Ramanathan]

Well, I ran a test and it showed that in ejbCreate method of a stateless session bean using BMT, I can successfully get a transaction reference.

Below

 public void ejbCreate()
{
System.out.println("Ejb Create........");
try
{
System.out.println("......................................... "+ sessionCtx.getUserTransaction().getStatus());
}
catch(javax.transaction.SystemException sex)
{
sex.printStackTrace();
}
} 

And the spec(page 90) also states that we can use getUserTransaction() in the ejbCreate or ejbRemove methods of a stateless session bean using BMT.

[Aleena Rehman]

If a method runs in an unspecified transaction context, means if you use context.getUserTransaction(), the code is not portable. It may work for one server, but not for another. The spec does not mandate containers to ignite a transaction for the methods marked with "Unspecified Transaction Context"

My 2 Cents...
Regards,
Aleena

[Muthaiah Ramanathan]

The spec says we can. So that means it is portable, right?

[Imran Vohra]

I think spec is saying that you can call "getUserTransaction()" method in ejbCreate() & ejbRemove() of stateless bean BUT you cannot call "UserTransaction methods".

[suman.pulikond a]

if it is like that what is the benefit of getting usertransaction object, If we were unable to call any method in that one for BMP'S.