private static final EchoService singletonEchoService =
new EchoService(SockJsConfig.withPrefix("/echo").cookiesNeeded().build());
private static SockJsServiceFactory singletonEchoService() {
return new AbstractSockJsServiceFactory(singletonEchoService.config()) {
@Override
public SockJsService create() {
return singletonEchoService;
}
};