Hi!
I have a problem with hibernate. When i want to delete or edit an object, i have this exception:

"a different object with the same identifier value was already associated with
the session"

Yesterday, i modified the .hbm.xml because i had this exception:

"deleted object would be re-saved by cascade (remove deleted object from associations)"

I erased the property lazy="false" of my .hbm.xml, maybe it is the reason that now is failing...?

I am a spanish girl, sorry for my english, i hope you understand me.

Hi,

Plase check the cascade value.

cascade="all-delete-orphan"

i am using spring+hibernate, and my configuration file has this code:


<bean id="controladorAlumno" class="org.cisgalicia.control.controladores.ControladorAlumno">
<property name="alumnoServicio" ref="alumnoServicio" />
<property name="empresaServicio" ref="empresaServicio" />
<property name="cursoServicio" ref="cursoServicio" />
</bean>


Maybe, if i use three "Servicios" inside the same "controladorAlumno", they will share the same Hibernate Session, what do you think? it is posible?

Sounds like you are explicitly deleting an object that is part of a collection marked as cascade="all-delete-orphan" but not removing it from the collection. And perhaps doing an update on a detatched instance instead of a merge.

now i am doing a merge (not a update), and the application is running "better",not as well that i want, but better than few minutes ago, ;).
But i have another cuestion for this problem. I put this code in my web.xml:

<filter>
<filter-name>openSessionInViewFilter</filter-name>
<filter-class>
org.cisgalicia.sesion.MySessionFilter
</filter-class>
<init-param>
<param-name>singleSession</param-name>
<param-value>true</param-value>
</init-param>
<init-param>
<param-name>sessionFactoryBeanName</param-name>
<param-value>sessionFactory</param-value>
</init-param>
</filter>

<filter-mapping>
<filter-name>openSessionInViewFilter</filter-name>
<url-pattern>*.do</url-pattern>
</filter-mapping>

<filter-mapping>
<filter-name>openSessionInViewFilter</filter-name>
<url-pattern>*.jsp</url-pattern>
</filter-mapping>

It was because i needed to change de flush mode, and this is the class MySessionFilter. it is all ok in this class?

public class MySessionFilter extends OpenSessionInViewFilter {
protected Session getSession(SessionFactory sessionFactory)
throws DataAccessResourceFailureException {
Session session = super.getSession((org.hibernate.SessionFactory) sessionFactory);
session.setFlushMode(FlushMode.COMMIT);
return session;
}
protected void closeSession(Session session, SessionFactory factory) {
session.flush();
super.closeSession(session, (org.hibernate.SessionFactory) factory);
}
}

I've never used OpenSessionInViewFilter but having read the spring docs your code looks fine. Did you add this filter recently? I ask because there is a warning in the spring docs saying:

"Applying this filter to existing logic can cause issues that have not appeared before, through the use of a single Hibernate Session for the processing of an entire request. In particular, the reassociation of persistent objects with a Hibernate Session has to occur at the very beginning of request processing, to avoid clashes with already loaded instances of the same objects."

Adding this filter to existing code could lead to the exception you were seeing: "a different object with the same identifier value was already associated with the session"

Yes! I added this filter recently because i had an exception saying that the flushmode was only "to read". I could not save or update any object and i saw this solution searching in some forums.
There is another solution to change the flushmode?

This is the exception that caused that I changed flushmode:

Write operations are not allowed in read-only mode (FlushMode.NEVER/MANUAL): Turn your Session into FlushMode.COMMIT/AUTO or remove 'readOnly' marker from transaction definition

This probably means you were trying to delete/update objects inside a read-only transaction. I imagine the correct fix would be to change the transaction definition for the service operation you are performing, not to add a filter that overrides flush mode. How are you managing transactions? spring or ejb?

I am managing transactions with spring:

<!-- Transaction Manager -->
<bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory"><ref bean="sessionFactory"/></property>
</bean>

That's the transaction manager but how are transactions actually started? Are you using spring's declarative transactions?
e.g.

I don't understand what are you asking to me. Do you want to say properties of TransactionManager?

How do you begin a transaction in your system?

with getHibernateTemplate

For example:

public List<Alumno> getAlumnos() {
return getHibernateTemplate().find("from Alumno");
}


You talk about that?

Ok, because you don't know what I'm talking about I assume you're not using middle tier transactions at all. In which case, you should _keep_ your filter the way it is and fix any problems you have in the service layer.