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Hibernate calls flush on find- causes not-null error

Answer 1

+1 A:

Turn off auto-flushing on the Session object to fix this exception.

Session s;
// if you're doing transactional work
s.setFlushMode(FlushMode.COMMIT);
// if you want to control flushes directly
s.setFlushMode(FlushMode.MANUAL);

This is not your error however. Something earlier in your code is causing the in memory objects to be in an invalid state which is trying to be persisted to the DB during the autoflush.

Jherico 2009-05-22 18:27:48

I'm using annotations to mark transactional boundaries -- @Transactional(readOnly=false). I thought that this was the preferred way of handling boundaries rather than manually inside my code?Also, the entity is in an invalid state, but I'm not ready for it to be committed yet -- hibernate is doing that on it's own, during a SELECT. Why?

Marty Pitt 2009-05-22 18:33:17

Just because you're in a transaction doesn't mean that SQL isn't going to be executed against the database. FlushMode controls when the SQL gets executed, not when the transaction gets committed. If you're going to be creating objects that have invalid state as far as your database is concerned, you may need to defer flushing until a later time in the way that Jherico suggests.

cliff.meyers 2009-05-23 17:08:34

Answer 2

+2 A:

hibernate remembers with objects needs to be saved. when issuing a select, hibernate will flush these changes. this ensures the select will return the correct results.

setting flushmode to anything else than FlushMode.AUTO will prevent this behaviour. But the error is in your code, where you pass an incomplete object to hibernate to persist or update. So the correct solution is to pass the object later to hibernate, when it is complete.

Salandur 2009-05-22 18:49:26

While passing an incomplete object into hibernate is a good candidate for the null constraint violation, there are a lot of code paths that could trigger such an error, having to do with modification of items already in the session, so its not always obvious where the error is occuring.

Jherico 2009-05-23 02:07:13

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Hibernate calls flush on find- causes not-null error

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