private static boolean isComponent(JID jid) {
        final RoutingTable routingTable = XMPPServer.getInstance().getRoutingTable();
        if (routingTable != null) {
            return routingTable.hasComponentRoute(jid);
        }
        return false;
    }
Checks to see if the jid given is a component by looking at the routing
table. Similar to {@link InternalComponentManager#hasComponent(JID)}.

@param jid The address to look up.
@return {@code true} if the JID is a component, {@code false<.tt> if not.
xmppserver/src/main/java/org/jivesoftware/openfire/pubsub/PubSubEngine.java