@Override
    public void initialize(XMPPServer server) {
        super.initialize(server);
        localServer = server;
        serverName = server.getServerInfo().getXMPPDomain();
        routingTable = server.getRoutingTable();
        deliverer = server.getPacketDeliverer();
        presenceManager = server.getPresenceManager();
        rosterManager = server.getRosterManager();
        userManager = server.getUserManager();
    }
Determine and call the update method based on the item's subscription state.
<p/>

@param item      The item to be updated
@param action    The new state change request
@param isSending True if the roster owner of the item is sending the new state change request
xmppserver/src/main/java/org/jivesoftware/openfire/handler/PresenceSubscribeHandler.java