I think im confused a bit about session annotation in spring mvc.
I have code like this (2 steps form sample, step 1 user data, step 2 address)
@SessionAttributes({"user", "address"})
public class UserFormController {
@RequestMapping(method = RequestMethod.GET)
public ModelAndView show( ModelAndView mv ){
mv.addObject( new User() );
mv.addObject( new Address() );
mv.setViewName("user_add_page");
return mv;
}
@RequestMapping(method = RequestMethod.POST)
public String processForm( User user, BindingResult result ){
new UserValidator().validate(user, result);
if( result.hasErrors() ){
return "user_add_page";
}else{
return "redirect:/user_form/user_add_address";
}
// .........
}
Now if i submit page after my session expires i get error
org.springframework.web.HttpSessionRequiredException: Session attribute 'user' required - not found in session
How do i handle it? i would like to have 2 options
Im still in early stage of learning Spring so sorry if its something very obvious, i just cant see it.
ps. is that even the good way to solve this kind of form in spring mvc or would you recomment different approach?
1.i create empty objects if missing in session and accept submit
Use @ModelAttribute("user")
-annotated method to provide the default value
2.i forward back to user form with some message
Use @ExceptionHandler(HttpSessionRequiredException.class)
-annotated method
Try to check here:
http://forum.springsource.org/showthread.php?t=63001&highlight=HttpSessionRequiredException
@Controller
@RequestMapping(value="/simple_form")
@SessionAttributes("command")
public class ChangeLoginController {
@ModelAttribute("command")
public MyCommand createCommand() {
return new MyCommand();
}
@RequestMapping(method = RequestMethod.GET)
public String get() {
return "form_view";
}
@RequestMapping(method = RequestMethod.POST)
public String post(@ModelAttribute("command") MyCommand command) {
doSomething(command); // execute business logic
return "form_view";
}
}
According to the Spring 3.0 reference manual , it looks like @SessionAttributes is meant to be used on a type that you want to be stored transparently in the session, such as a "Command" or a form-backing object. I don't think you would want to store a Controller in session.
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