// Cancel unsubscriberJID's subscription to recipientJID's PEP service, if it exists.
CollectionNode rootNode = pepService.getRootCollectionNode();
NodeSubscription nodeSubscription = rootNode.getSubscription(unsubscriber);
if (nodeSubscription != null) {
rootNode.cancelSubscription(nodeSubscription);
}
}
/**
* Implements UserItemsProvider, adding PEP related items to a disco#items