Don't dereference a collection with cascade="all-delete-orphan"

[ashish.abrol]

Hi,
I have a very weird problem. I have a method doSomething() in a java application implemented in Spring. When I run the method without putting any decalarative transactions in the application-context.xml it works fine. But the moment I put the transactions like <prop key="doSomething">PROPAGATION_REQUIRED</prop> I start getting the error that says "Don't dereference a collection with cascade="all-delete-orphan": A.myCollection". If I change the cascade attribute to "all" instead of "all-delete-orphan" it starts working and I donot get any error. But I need to know that if the function works fine with "all-delete-orphan" cascade without using transactions, then why does it fail when I add transactions to it.



Hibernate version:3.0

I have a class A wherein I have a collection of instances of class B in the following manner-


Class-> class A{
private List myCollection;

public void writeMyCollection(List myCollection) {
this.myCollection = myCollection;
}

}

Mapping documents->
<class name="A" table="A">
<id name="id" type="long" column="ID" unsaved-value="0">
<generator class="native"/>
</id>
<list lazy="true" name="myCollection" access="field" cascade="all-delete-orphan">
<key column="SOME_ID"/>
<index column="SORT_INDEX"/>
<one-to-many class="B"/>
</list>
</class>



Code between sessionFactory.openSession() and session.close():->
public void doSomething(long id, List collection){
A a = (A) this.getHibernateTemplate().get(A.class,
new Long(Id));
a.writeMyCollection(collection);

}


Full stack trace of any exception that occurs:->
org.springframework.orm.hibernate3.HibernateSystem Exception: Don't dereference a collection with cascade="all-delete-orphan": A.myCollection; nested exception is org.hibernate.HibernateException: Don't dereference a collection with cascade="all-delete-orphan": A.myCollection
org.hibernate.HibernateException: Don't dereference a collection with cascade="all-delete-orphan": A.myCollection
at org.hibernate.engine.Collections.processDereferenc edCollection(Collections.java:70)
at org.hibernate.engine.Collections.processUnreachabl eCollection(Collections.java:38)
at org.hibernate.event.def.AbstractFlushingEventListe ner.flushCollections(AbstractFlushingEventListener .java:211)
at org.hibernate.event.def.AbstractFlushingEventListe ner.flushEverythingToExecutions(AbstractFlushingEv entListener.java:71)
at org.hibernate.event.def.DefaultAutoFlushEventListe ner.onAutoFlush(DefaultAutoFlushEventListener.java :39)
at org.hibernate.impl.SessionImpl.autoFlushIfRequired (SessionImpl.java:711)
at org.hibernate.impl.SessionImpl.prepareQueries(Sess ionImpl.java:895)
at org.hibernate.impl.SessionImpl.getQueries(SessionI mpl.java:885)
at org.hibernate.impl.SessionImpl.list(SessionImpl.ja va:834)

Please let me know if you need any more details or anything is not clear.

Thanks in Advance,
Ashish Abrol

[Costin Leau]

What version of hibernate are you using? In 3.1.3 I see the exception line being removed.

[ashish.abrol]

Thanks so much. After downloading Hibernate's 3.1.3 version I am no longer facing this issue and the problem seems fixed.

Regards,
Ashish Abrol

[mpuhlmann]

Hello,

in my opinion it's not a problem with the hibernate version itselfs. You try to change the reference to the collection inside an object of type A. But this collection is mapped using "delete-all-orphan". A better solution would be to do something like that:

public void writeMyCollection(List myCollection) {
...
this.myCollection.clear();
this.myCollection.addAll(myCollection);
...
}

Take also a look at the following link: http://www.hibernate.org/117.html#A3

Hope i could help you

Best regards,

M. Puhlmann

[jcgagne]

This thread is rather old but maybe the following could help.

I had the same problem without ever touching the reference to the collection. It appears that the problem came from a bad transaction configuration.

I use BeanNameAutoProxyCreator to wrap some beans in a TransactionInterceptor. One of those beans should not be wrapped, but its original name matches the patterns I specified. The business process uses that bean, giving unexpected transactional behaviour causing the problem.

Just renaming the bean made my day.

JCG