Making Spring 3 MVC controller method Transactional

Question

I am using Spring 3.1 and have my DAO and service layer(transactional) written.

However in a special case to avoid a lazy init exception I have to make a spring mvc request handler method @transactional. But It is failing to attach transaction to that method. Method name is ModelAndView home(HttpServletRequest request, HttpServletResponse response). http://forum.springsource.org/showthread.php?46814-Transaction-in-MVC-Controller From this link it seems it is not possible to attach transaction (by default ) to mvc methods. Solution suggested in that link seems to be for Spring 2.5 (overriding handleRequest ). Any help will be reallyappreciated. Thanks

@Controller
public class AuthenticationController { 
@Autowired
CategoryService categoryService;    
@Autowired
BrandService brandService;
@Autowired
ItemService itemService;

@RequestMapping(value="/login.html",method=RequestMethod.GET)
ModelAndView login(){       
    return new ModelAndView("login.jsp");       
}   
@RequestMapping(value="/home.html",method=RequestMethod.GET)
@Transactional
ModelAndView home(HttpServletRequest request, HttpServletResponse response){
    List<Category> categories = categoryService.readAll();
    request.setAttribute("categories", categories);     
    List<Brand> brands = brandService.readAll();
    request.setAttribute("brands", brands);     
    List<Item> items = itemService.readAll();
    request.setAttribute("items", items);
    Set<Image> images = items.get(0).getImages();
    for(Image i : images ) {
        System.out.println(i.getUrl());
    }
    return new ModelAndView("home.jsp");    
}

What you are trying to rollback here? On the controller function where you have defined the @Transaction annotation there is no such database operation that can be rolled back. Im confused. — Japan Trivedi
all the service calls like categoryService.readAll() are database operations — Subin Sebastian
Ya but you can not roll back the read data. What are you exactly trying to roll back? — Japan Trivedi
It is still useful to wrap the home method in a transaction as it'll help in sharing database connections potentially — Kieran
yes good point that connections will be shared, also lazy loading works only within same session. — Subin Sebastian

Kieran Kieran · Accepted Answer · 2012-10-19T10:05:27

You'll need to implement an interface so that Spring has something it can use as a Proxy interface:

@Controller
public interface AuthenticationController {
  ModelAndView home(HttpServletRequest request, HttpServletResponse response);
}

@Controller
public class AuthenticationControllerImpl implements AuthenticationController {

@RequestMapping(value="/home.html",method=RequestMethod.GET)
@Transactional
@Override
ModelAndView home(HttpServletRequest request, HttpServletResponse response){
.....
}
}

Making Spring 3 MVC controller method Transactional

3 Answers