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How to decompose a model in controllers?

Using Spring MVC, is there a factorization way org.springframework.ui.Modelto not specify it in the method parameters in any controller?

In other words, I am doing it like this:

public abstract class AbstractController {

    @Autowired
    protected MultipartHttpServletRequest request;

}

@Controller
public class SigninController extends AbstractController {

    @RequestMapping(value = "/signin", method = RequestMethod.GET)
    public String signin(@ModelAttribute User user, Model model) {
        // do stuff with user (parameter)
        // do stuff with model (parameter) <--
        // do stuff with request (attribute)
        return "/signin/index";
    }

}

And I would like to do like this:

public abstract class AbstractController {

    @Autowired
    protected MultipartHttpServletRequest request;

    @Autowired
    protected Model model;

}

@Controller
public class SigninController extends AbstractController {

    @RequestMapping(value = "/signin", method = RequestMethod.GET)
    public String signin(@ModelAttribute User user) {
        // do stuff with user (parameter)
        // do stuff with model (attribute) <--
        // do stuff with request (attribute)
        return "/signin/index";
    }

}

But when calling the url, an exception is thrown:

...Could not autowire field: protected org.springframework.ui.Model...
...No matching bean of type [org.springframework.ui.Model] found for dependency...

I got the same error when using org.springframework.ui.ModelMap.

Any brilliant solution?

Thanks for the help:)

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1 answer

I finally found a solution. I'm not sure the game is worth it, but it works :)

First add these things to your AbstractController:

public abstract class AbstractController {

    @Autowired
    protected MultipartHttpServletRequest request;

    protected ModelMap model;

    public void setModel(ModelMap model) {
        this.model = model;
    }

    public ModelMap getModel() {
        return model;
    }

}

Then create an interceptor that implements org.springframework.web.servlet.HandlerInterceptor, like this one:

public class UserContextInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws ServletException {
        if (handler instanceof AbstractController) {
            AbstractController controller = (AbstractController) handler;
            controller.setModel(new ModelMap());
        }
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) {
        if (handler instanceof AbstractController && modelAndView != null) {
            AbstractController controller = (AbstractController) handler;
            modelAndView.addAllObjects(controller.getModel());
        }
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
    }

}

Finally, add these lines to your applicationContext.xml:

<mvc:interceptors>
    <bean class="path.to.my.just.created.UserContextInterceptor" />
</mvc:interceptors>

, , , AbstractController.

! request, model :) , . :)

, .

+1

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