Hi All

It is highly appreciated if someone give offer answers to my below questions

1) There are two ways of locking mechanism: Pessimistic & Optimistic. In general, do all J2EE app server support all these two ways of locking ?

2) It seems to me that setting the isolation level to "serialization" should result in using pessmistic locking. If no so, please point out my misconcept and explain to me.

3) Are there any differences in the way of entity bean programming as different locking mechansim is adopted ?

4) With regard to optimistic locking, will the app server throw out exception as data contention is detected ? Is the way of handling dependent on app server? Or It is transparent to the developer of entity bean. Please give me an e.g of j2ee app server product how to handle this scenario.

5) To adopt the approach of "optimistic" locking, do l have to implement it on my own using bean managed entity bean.

6) It seems to me that optimistic locking can achieve better concurrency. If it is inherently supported by app server for its container managed entity bean (=> totally transparent to the developer of entity bean). Is it always the rule of thumb to config the server to use "optimistic" locking instead of "pessimistic" ?

Sorry for bombarding you guys with such long list of questions. l would be very thankful if someone can help me consolidate my concept on these topics.

Also, please send your reply to cwso7 at netscape dot net as well

thanks & regards