private XMPPCoreStanza handleInboundPresenceProbe(PresenceStanza stanza, ServerRuntimeContext serverRuntimeContext,
SessionContext sessionContext, ResourceRegistry registry, RosterManager rosterManager) {
Entity contact = stanza.getFrom();
Entity user = stanza.getTo();
RosterItem contactItem;
try {
contactItem = rosterManager.getContact(user, contact.getBareJID());
} catch (RosterException e) {
contactItem = null;
}
if (contactItem == null || !contactItem.hasFrom()) {
// not a contact, or not a _subscribed_ contact!
relayStanza(contact, buildPresenceStanza(user, contact, UNSUBSCRIBED, null), sessionContext);
return null;
}