@OptimisticLock(excluded=true) doesn't work for detached obj

Michel · **Joined:** Mon Nov 20, 2006 12:41 pm **Posts:** 4

Hibernate version:3.2.3.ga
Hibernate Annotation version:3.3.0.GA

I'm facing a strange behaviour. I have an versionned entity and one attribute annotated as @OptimisticLock(excluded=true). I'm only changing the attribute wich is excluded from the optimstic lock. Then I try to update it. If I made the change on a persistant instance the version is not incremented at the flush() but if I made the change on a detached object (an object which was in a Session but was evicted from it) and call the update method on a new Session the version is incremented but it shouldn't.

I didn't test it with xml mapping but I would like to know if it's the correct behaviour or a bug?

My entity has several one-to-many relationships and the attribute which is annotated as @OptimisticLock(excluded=true) is also @Embbeded

Code:

@Entity
public class Car {
   ...
   @Id
   public Long getId() {
   ...

   @Version
   public Long getVersion() {
   ...

   @Embedded
   @OptimisticLock(excluded=true)
   public Engine getEngine() {
   ...

   ...
}

This case doesn't increment the version

Code:

// open session and begin transaction
Car car = session.get(Car.class, id);
car.setEngine(new Engine());
// flush the session

This case increment the version and it should't do it

Code:

// open session and begin transaction
Car car = session.get(Car.class, id);
car.setEngine(new Engine());
...
session.evict(car);
...
session.update(car);
// flush the session 

emmanuel · **Posted:** Thu Aug 30, 2007 5:28 pm

This is the correct behavior since we don't know the old object state, so we assume everything has changed.
One way to avoid that is to use merge

Michel · **Joined:** Mon Nov 20, 2006 12:41 pm **Posts:** 4

Thanks for your previous answer. It didn't fully solve my problem. I'm going to explain my case.

I'm in an EJB and my clients doesn't provide me the full object graph so I have to load the data from the db, change them according to the partial object I received and update them. According to the paragraph 11.3.1 in the documentation , I have to check the version manually. My question is : Can Hibernate do automatically the version checking in this case because the partial object I receive is not trivial to check?

Code:

public void update(Car car){
// open session and begin transaction
Car carDb = session.get(Car.class, car.getId());

// map all the changes I need
carDb.setName(car.getName()); // a String attribut
carDb.setEngine(car.setEngine()); // a complex Object
carDb.setVersion(car.getVersion());
// -> I want to keep all others attributs and relationship as in the db

// flush the session
}

I would like that Hibernate fire the version checking at the flush but it doesn't.

I've also tried a dirty solution as a session.evict(carDb); session.update(carDb); or a session.evict(carDb);session.merge(carDb); before the flush but it didn't do what I want.

Is there any solution or any pattern to follow in this case in order to "say" to Hibernate to do the version checking?

emmanuel · **Posted:** Wed Sep 19, 2007 5:20 pm

not really, because you are not supposed to change the version manually as your code does.