In setting a bidirectional assoiation, for example Child/Parent relation, if only set one direction:

child.setparent(parent) // leave out code: parent.addchild(child)
session.save(child)

Then retrieve the assoiation:

child.getParent() is OK

parent.getChildren() is empty.

And the data in DB ,"parent_id" is correct.

But if close current session, and open a new seesion, parent.getChildren() returns is correct.

I think when the save operation is successful, Hibernate only update the

database,the other assoiation end in cache (first-level cache) is not

refreshed . It is the expected behavior??????

I have tried the session.get() and session.load(). They can not solve my problem. How can I synchronize the database and the cache????

yes it is!
this is your job to manage the java model integrity.
You have to explicitly set both ends of a bidirectional association.

There is a best practice described in Hibernate in action (just some smart code to add in the setter or addChild method)