Is forceUpdateToVersionField only for Root UoW?

Question

Dear all,
We would like force update to the version field when it's privately owned object get changes. It is our developed function.
public static void addOrUpdateObject(Session session, Object obj) {
     session.removeFromIdentityMap(obj);
     Object objFromDB = getObjectByOid(session, obj); // read the object from database.
     UnitOfWork uow = session.acquireUnitOfWork();
     uow.registerObject(objFromDB); // register the object retreived from DB.
     // merge the changes from pObj.
     Object pObjClone = uow.mergeCloneWithReferences(obj);
     // force to update version field only when pObj has been changed.
     uow.forceUpdateToVersionField(pObjClone,uow.hasChanges());
     uow.commit();
And we want to extend the function for multiple object as following.
public static void addOrUpdateObject(Session session, List objList) {
     List objListFromDB = new ArrayList();
     for (int i=0; i<objList.size(); i++) {
          Object obj = objList.get(i);
          session.removeFromIdentityMap(obj);
          objListFromDB.add(getObjectByOid(session, obj.getClass(), obj.getOid()));
     UnitOfWork uow = session.acquireUnitOfWork(); // acquire the unit of work.
     for (int i=0; i<objList.size(); i++){
          UnitOfWork subUoW = uow.acquireUnitOfWork();
          subUoW.registerObject(objListFromDB.get(i)); // register the object retreived from DB.
          // merge the changes from obj.
          Object objClone = subUoW.mergeCloneWithReferences(objList.get(i));
          // force to update version field only when obj has been changed.
          uow.forceUpdateToVersionField(objClone,subUoW.getChanges().hasChanges());
          subUoW.commit();
     uow.commit();
However, we found the verion field is not updated. Is it because we only can apply forceUpdateToVersionField() to only root UoW?
Thanks and regards,
William

Answer 1

First I would recommend against removing objects from the identity map (cache) as this will result in objects in memory not referencing the correct instances of objects. If it is an absolute requirement then be sure you are removing the entire object tree that that object is a member of.
Currently the forceUpdateToVersionField is only available on the root UnitOfWork. I have entered a change request to have this functionality moved to nested UnitOfWorks as well.
--Gordon