I am using Hibernate in Spring MVC 3.05 and an Oracle database.
I have a transaction in which I insert a new record into two tables: User and Registration.
Registration contains a UserId (meaning a user may have many registrations).
When I commit the transaction, I can query my database and see that the new rows were successfully inserted.
The problem
After the transaction commits successfully, I redirect the user to a confirmation page, where I would like to show some information about the registration that was just inserted. On the confirmation page, I do a Hibernate query by userId to get the User that was just inserted. I then use the following properties to populate my model:
- User.getName()
- User.getEmail()
- User.getBlah()
- User.getReigstrations().iterator.next()
The one in bold throws an exception “NoSuchElementException” because there are no items in the set. There should be one Registration in the set. If I close the browser, start a new one, and direct myself back to the same link that threw the exception, IT WORKS! There is a Registration in the set.
My guess is that it’s not reloading related table objects when I query for my User, but is either pulling from cache or assuming that nothing more had been added since the User was saved. Does anyone know of a way to force Hibernate to reload this data?
Unfortunately I can’t just get a Registration by UserId because it maps UserId to the entire User object (via object generation because User is a foreign key).
Hope this makes sense. Any help is appreciated. I am open to a different approach to accomplishing this as well. Thanks!
It’s hard to diagnose the exact problem because you don’t say when you close sessions, and in which session/transaction you get your User. But I guess the problem comes from the fact that you don’t maintain the two sides of the relationship when inserting a new registration.
You should set the user in the registration, and add the registration to the list of registrations of the user.