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Stateless Session Bean

Edy Yu
Ranch Hand

Joined: Nov 21, 2000
Posts: 264
Here is what I understand it:
If I have a instance varible in the stateless session bean and I have two methods. The bean/container won't maintain the instance varible for me between the two method calls. But I tested the scenario in the J2ee server. It appears that the server is maintaining that for me.
Can anybody explain this for me?
Thanks in advance.

SCJP, SCJD, SCWCD, SCBCD, SCEA, IBM Certified Enterprise Developer, WebSphere Studio V5.0
Tim Holloway
Saloon Keeper

Joined: Jun 25, 2001
Posts: 17417

I think you're confusing "not throwing an exception" with maintaining.
You CAN define static variables - or preferably constants, providing you're willing to deal with the multi-tasking consequences. However, instance variables are tied to specific instances, and instances are created, recycled, and destroyed according to rules that don't guarantee that any two invocations - whether from the same client or another - will receive the same instance. The heavier the workload, the more likely that your application will fail unpredictably.
A *REALLY* picky appserver could check the EJB's class files and refuse to deploy anything with instance variables, but regardless, there is a reason why there's a separate type of session EJB for when you need to maintain state.
[ June 10, 2002: Message edited by: Tim Holloway ]

An IDE is no substitute for an Intelligent Developer.
It is sorta covered in the JavaRanch Style Guide.
subject: Stateless Session Bean
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