Concurrent entity beans access

Question

I have failed to come up with a workable solution for concurrent entity bean access on the SUN reference implementation together with cloudscape.
I have created a test case and a webpage which describes my problem. If anyone can come up with a working solution (must work on the RI) I would be very thankful.
Please have a look at
http://www.offermanns.de/~rolf/ejb-concurrency/
and tell me what you think.
-Rolf

Answer 1

Hi,
I thought that this is a problem. But this isn't just
about this pattern. It is a general question about how
to get concurrent access to entity beans to work on
the RI.Entity Beans are the shared components , same instance is being shared between all the concurrent users so if the same component is a part of the longer transaction then the component can lead to the data corruption and to avoid that you have to set the ISOLATION Level for the concurrent running long transactions.Remember the Entity beans are shared components and are shared between all the cliens not like the Sessoin BEans where different clients can get different instances.
I tried to alter the cloudscape setting to SERIAZABLE,
but that won't help. (from the cloudscape log, it
seems, that the container switches back to READ_COMMIT
before every transaction.You dont have to change the setting in the Cloudscape,you require add the Isolation-level tag in the deployment descriptor.These can take the values as
1)READ_COMMITED
2)READ_UNCOMMITTED
3)REPEATABLE_READ
4)SERIALIZABLEI hope this will help.
Regards
Vicky