@Override
    public void start() {
        // Set this ComponentManager as the current component manager
        ComponentManagerFactory.setComponentManager(instance);

        XMPPServer server = XMPPServer.getInstance();
        serverDomain = server.getServerInfo().getXMPPDomain();
        // Set the address of this internal service. component.[domain]
        serviceAddress = new JID(null, "component." + serverDomain, null);
        if (!server.isSetupMode()) {
            // Add a route to this service
            server.getRoutingTable().addComponentRoute(getAddress(), this);
        }
    }
Holds the domain of the server. We are using an iv since we use this value many times
in many methods.
xmppserver/src/main/java/org/jivesoftware/openfire/component/InternalComponentManager.java