[eclipselink-users] control order of em.remove() calls

[Christian Menz <christianmenz@xxxxxxxxxx>]

Dear all,

I have an issue I can't solve.
My data structure has a parent child relation, like..

class A {

	A parent;

	List<A> children (cascade=ALL)
}

Now I want to remove a part of the tree. As far as I understand the order of the delete statements is essential. What I actually do is a recursive method that deletes all the instances beginning from the leaves.

This looks more or less like :

remove(A a) {

       recursiveRemove(a);
       a.parent.children.remove(a);

}

removeRecursive(A a) {

	for all children of a {
		removeRecursive(a);
		a.parent.children.remove(a);
	}

	entityManager.remove(a);
}

I know the entityManager.remove() calls come in in the correct (leaf first) order, but JPA seems to execute in another order. It tries to delete the parent first, which causes a violation of the constraint.

Am I completely on the wrong path or is there a way to control execution order of JPA-statements for such parent/child relations? I thought that should be the case anyways.. :)

BTW. when just letting JPA remove the data with em.remove(rootA) I get the same problem. That is actually why I implemented the recursive call.

Thank you very much for your support.