I have a problem. I want to write an application using long running transactions.
My usecase is with several steps:
1. I want to create and persist an object
2. This object is subsequently changed
3. At the end I want to save (flush) changes to the database.
To achieve this behavior I tried to use PersistentContext in EXTENDED mode. I have written stateful session bean which implements all steps. This did not work so I have tried how TraiBlazer application is working
In the module Runtime services ? Application transactions ? there is an example of stateful session bean running with a persistent context in the extended mode.
@Stateful
public class ApptransCalculator implements Calculator, Serializable {
@PersistenceContext(
type=PersistenceContextType.EXTENDED
)
protected EntityManager em;
// ... ...
}
In the example the flush and commit to the database should happen only when the checkout method is called. In example the checkout method is called in the update2.jsp (check.jsp). I have repacked the EJB3Trail.ear with some changes:
1. I enabled show_sql property for Hibernate.
2. I have changed the datasource to oracle.
I monitored the changes in the database after each step. I found out that it behaves not as the example is trying to show. The click on update button on update.jsp (calculator.jsp) writes to the database. Now the question is: Am I understanding something wrong or is these just not working as it should? As I understand flush should happen when checkout method (which is annotated with @Remove) is called.
Thanks
Peter Repinc
