WebSocketController { @MessageMapping("/vehicle/{id}/capacity") void changeCapacity(@DestinationVariable long id, int capacity) { vehicleService.changeCapacity(id, capacity); } @Autowired  WebSocketController(
            RouteListener routeListener,
            RegionService regionService,
            LocationService locationService,
            VehicleService vehicleService,
            DemoService demoService,
            ApplicationEventPublisher eventPublisher);   }
@Test void changeCapacity() { long vehicleId = 2000; int capacity = 50; webSocketController.changeCapacity(vehicleId, capacity); verify(vehicleService).changeCapacity(vehicleId, capacity); }