public void setAssociationPolicy(CollectionNode.LeafNodeAssociationPolicy associationPolicy) {
        this.associationPolicy = associationPolicy;
    }
Sets the policy that defines who may associate leaf nodes with a collection.

@param associationPolicy the policy that defines who may associate leaf nodes
       with a collection.
xmppserver/src/main/java/org/jivesoftware/openfire/pubsub/DefaultNodeConfiguration.java