14 Tips for Writing Spring MVC Controllers

Spring MVC is a Java web framework that uses controller classes to process client requests, invoke business logic, and return logical view names. The article provides fourteen concise tips to help developers write clean, maintainable, and functional Spring MVC controllers.

1. Use @Controller annotation

Mark a class with @Controller and map request URLs with @RequestMapping .

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class HomeController {
    @RequestMapping("/")
    public String visitHome() {
        return "home";
    }
}

2. Implement the Controller interface

For a classic approach, let the class implement org.springframework.web.servlet.mvc.Controller and override handleRequest .

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.Controller;

public class MainController implements Controller {
    @Override
    public ModelAndView handleRequest(HttpServletRequest request,
                                    HttpServletResponse response) throws Exception {
        System.out.println("Welcome main");
        return new ModelAndView("main");
    }
}

3. Extend AbstractController

When you need fine‑grained control over HTTP methods, sessions, or caching, extend AbstractController .

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.AbstractController;

public class BigController extends AbstractController {
    @Override
    protected ModelAndView handleRequestInternal(HttpServletRequest request,
                                                HttpServletResponse response) throws Exception {
        System.out.println("You're big!");
        return new ModelAndView("big");
    }
}

4. Specify URL mapping with @RequestMapping

Use @RequestMapping("/login") at class or method level to bind URLs.

5. Define HTTP methods

Set the method attribute to restrict handling to GET, POST, etc.

@Controller
public class LoginController {
    @RequestMapping(value="/login", method=RequestMethod.GET)
    public String viewLogin() {
        return "LoginForm";
    }
    @RequestMapping(value="/login", method=RequestMethod.POST)
    public String doLogin() {
        return "Home";
    }
}

6. Bind request parameters

Use @RequestParam to map query or form parameters to method arguments.

@RequestMapping(value="/login", method=RequestMethod.POST)
public String doLogin(@RequestParam String username,
                      @RequestParam String password) {
    // authentication logic
    return "Home";
}

7. Return ModelAndView or view name

Return a view name directly or a ModelAndView object to pass data to the view.

@RequestMapping("/listUsers")
public ModelAndView listUsers() {
    List
listUser = new ArrayList<>();
    ModelAndView mv = new ModelAndView("UserList");
    mv.addObject("listUser", listUser);
    return mv;
}

8. Add objects to the model

Use model.addObject(...) or a Map parameter to expose data.

9. Perform redirects

Return "redirect:/login" to send the client to another URL.

10. Handle form submission and validation

Annotate a method with @ModelAttribute and check BindingResult for errors.

@Controller
public class RegistrationController {
    @RequestMapping(value="/doRegister", method=RequestMethod.POST)
    public String doRegister(@ModelAttribute("userForm") User user,
                              BindingResult bindingResult) {
        if (bindingResult.hasErrors()) {
            // handle errors
        }
        // registration logic
        return "Success";
    }
}

11. File upload

Accept CommonsMultipartFile[] parameters and transfer files.

@RequestMapping(value="/uploadFiles", method=RequestMethod.POST)
public String handleFileUpload(@RequestParam CommonsMultipartFile[] fileUpload) throws Exception {
    for (CommonsMultipartFile aFile : fileUpload) {
        aFile.transferTo(new File(aFile.getOriginalFilename()));
    }
    return "Success";
}

12. Autowire business services

Inject service or DAO beans with @Autowired .

@Controller
public class UserController {
    @Autowired
    private UserDAO userDAO;
    // handler methods delegate to userDAO
}

13. Access HttpServletRequest/Response

Declare HttpServletRequest and HttpServletResponse as method parameters.

@RequestMapping("/download")
public String doDownloadFile(HttpServletRequest request, HttpServletResponse response) {
    // use request/response streams
    return "DownloadPage";
}

14. Follow the Single Responsibility Principle

Keep controllers thin, delegate business logic to service/DAO layers, and create separate controllers for distinct domains (e.g., UserController, OrderController).

These fourteen tips help developers create Spring MVC controllers that are clear, testable, and aligned with best‑practice architecture.