l.setPrimaryProxy(primaryProxy);
    private Listener createListener(String address, int port, HttpUrl base, String simulator, boolean usePlugins) throws IOException {        if (base != null && base.equals("")) {            base = null;        }        if (simulator == null || simulator.trim().equals("") || !_simulators.containsKey(simulator)) {            simulator = "Unlimited";        }        NetworkSimulator netsim = (NetworkSimulator) _simulators.get(simulator);                Listener l = new Listener(this, address, port);        l.setBase(base);        l.setSimulator(netsim);        l.usePlugins(usePlugins);                String key = l.getKey();        _listeners.put(key, l);                if (_ui != null) _ui.proxyAdded(key);                return l;    }