Also,
Figured out that, in spring, if
a transaction is writable, i.e. readOnly=false, an early transaction is started
on the current UoW. The code is
if
(!definition.isReadOnly() && !this.lazyDatabaseTransaction) {
// This is the
magic bit. As with the existing Spring TopLink integration,
// begin an
early transaction to force EclipseLink to get a JDBC Connection
// so that
Spring can manage transactions with JDBC as well as EclipseLink.
UnitOfWork
uow = (UnitOfWork) getSession(entityManager);
uow.beginEarlyTransaction();
}
And it is writable, an early
transaction is started and the changes done to the parent are lost during
merge. I couldn’t figure out how this changes the behavior, but looks
like it does.
Can somebody please throw some
light on this?
Thanks,
Shashi
From:
eclipselink-users-bounces@xxxxxxxxxxx
[mailto:eclipselink-users-bounces@xxxxxxxxxxx] On Behalf Of Shashikant
Kale
Sent: Tuesday, July 27, 2010 2:34 PM
To: EclipseLink User Discussions
Subject: [eclipselink-users] Strange issue in merging changes.
Hi,
We have been using Eclipselink 1.2.0 with Spring.
We have configured Spring transaction interceptor (Using
@Transactional(readOnly=false)) to manage the transactions in our Service code.
Parent {
@OneToMany(mappedBy="parent",
cascade={CascadeType.ALL}, fetch=FetchType.EAGER)
@org.eclipse.persistence.annotations.PrivateOwned
protected List<Child>
children = new ArrayList<Child>();
}
Child {
@ManyToOne(cascade={CascadeType.REFRESH}) @JoinColumn(name="SOME_CHILD_ID")
protected Parent parent;
}
Service {
@Transactional (readOnly=false)
public void serviceMethod (Parent parent){
parent.setData(“data”);
……
……
Parent merged = em.merge(parent);
// Here the merged parent has lost the changes i.e. data
}
}
However I am seeing a strange issue in merging the changes
for an entity which has a child entity with OneToMany relation. The changes
done to the entity are getting lost. When I debugged into EL code, I went
inside merge code where changes are calculated for an entity, however in
org.eclipse.persistence.internal.descriptors.ObjectBuilder class I find that
when the OneToMany mapping is being merged in the method while traversing
through the DatabaseMapping, it calls further to merge changes in the Child,
the target entity instance i.e. child entity instance doesn’t contain the
latest parent entity with the changes. Hence the changes of the parent are
getting lost.
public void mergeIntoObject(Object target, boolean
isUnInitialized, Object source, MergeManager mergeManager, boolean cascadeOnly,
boolean isTargetCloneOfOriginal)
However if I remove CascadeType.REFRESH in the ManyToOne
mapping inside Child it works fine. Also if I mark the service method as
@Transactional (readOnly=true) it works fine either.
Is there anything wrong in the entity relationship setup?
Kindly let me know.
TIA,
Shashi