Originally posted by yamini nadella:
If entity bean transaction attribute is Never or Not supported then is it possible to update or create entity beans(update or delete records)?
You can still do data manipulation but you won't have access to a transaction and therefore you have no way to force or detect a rollback.
Never, NotSupported and Supported (without a pre-existing transaction) execute in an �an unspecified transaction context�. The spec leaves it to the server vendors to do as they seem fit - there could actually be a transaction out there, however you don't know, and even if you did, you couldn't access the transaction. see:
Enterprise JavaBeans Specification, Version 2.0
Chapter 17 Support for Transactions
17.6.5 Handling of methods that run with �an unspecified transaction context�
...
The EJB specification does not prescribe how the Container should manage the execution of a method with an unspecified transaction context�the transaction semantics are left to the Container implementation.
...
A failure that occurs in the middle of the execution of a method that runs with an unspecified transaction context may leave the resource managers accessed from the method in an unpredictable state. The EJB architecture does not define how the application should recover the resource managers� state after such a failure.
Originally posted by yamini nadella:
is this transaction attribute is for entire entity bean or per method?
Neither NotSupported nor Never is different in the DD configuration to the remaining four transaction attributes.
They
may apply to the entire bean if the wildcard is used and no more specifics have been configured (see below).
So Never and NotSupported could actually be applied to a single method and even a single method with a specific signature.