callbackConnector.start();
assertTrue(callbackConnector.isStarted());
assertFalse(callbackConnector.getServerInvoker().isStarted());
assertTrue(MultiplexServerInvoker.getSocketGroupMap().containsKey("id"));
AddressPair addressPair = new AddressPair("localhost", connectPort, "localhost", freePort);
assertFalse(MultiplexServerInvoker.getAddressPairMap().containsKey(addressPair));
int CLIENT_COUNT = 5;
Client[] clients = new Client[CLIENT_COUNT];
String locatorURI = serverLocatorURI + "/?clientMultiplexId=id";