public class GWTServiceImpl extends RemoteServiceServlet implements GWTService {
    
    @Autowired
    private OrderService orderService;
    
    @Override
    public void init(ServletConfig config) throws ServletException {
        super.init(config);
      WebApplicationContextUtils.getWebApplicationContext(config.getServletContext()).getAutowireCapableBeanFactory().autowireBean(this);

    }

<!--GWT -->
  <servlet>
        <servlet-name>GWTService</servlet-name>
        <servlet-class>ru.gwt.server.GWTServiceImpl</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>GWTService</servlet-name>
        <url-pattern>/gwt/gwtservice</url-pattern>
    </servlet-mapping>
 <!--GWT -->

@Controller
@RequestMapping("/gwt/gwtservice")
public class GWTServiceImpl extends RemoteServiceServlet implements GWTService {

    @RequestMapping(method = RequestMethod.GET)
    @ResponseBody
    public String gwtPage() {
        return "hello word";
    }

@RepositoryRestResource(collectionResourceRel = "order", path = "order")
public interface RestOrderRepository extends PagingAndSortingRepository<Order, Long>{

 }

    @Override
    public String processCall(String payload) throws SerializationException {
        try {
            RPCRequest rpcRequest = RPC.decodeRequest(payload, this.remoteServiceClass , this);
            // delegate work to the spring injected service
            onAfterRequestDeserialized(rpcRequest);
            //return  RPC.invokeAndEncodeResponse(this.remoteService, rpcRequest.getMethod(), rpcRequest.getParameters() ,new PortalLegacySerializationPolicy());
            return  RPC.invokeAndEncodeResponse(this.remoteService, rpcRequest.getMethod(), rpcRequest.getParameters() ,rpcRequest.getSerializationPolicy());
        } catch (IncompatibleRemoteServiceException ex) {
            getServletContext().log("An IncompatibleRemoteServiceException was thrown while processing this call.", ex);
            return RPC.encodeResponseForFailure(null, ex);
        }
    }