Question

An item is displayed at this URL:

/item/10101

using this Controller method:

@RequestMapping(value = "/item/{itemId}", method = RequestMethod.GET)
public final String item(HttpServletRequest request, ModelMap model, 
    @PathVariable long itemId)
{
    model = this.fillModel(itemId);
    return "item";
}

The page contains a form that submits to the following method in the same controller:

@RequestMapping(value = "/process_form", method = RequestMethod.POST)
public final String processForm(HttpServletRequest request,
 @ModelAttribute("foo") FooModel fooModel,
    BindingResult bindResult,
    ModelMap model)
{

    FooModelValidator validator = new FooModelValidator();
    validator.validate(FooModel, bindResult);

      if (bindResult.hasErrors())
      {
        model = this.fillModel(fooModel.getItemId());
       return "item";
      }
    return "account";
}

If the validator finds errors in the form, it redisplays the item but instead of displaying it at the original url:

/item/10101

it displays it at its own url:

/process_form

Is it possible to redisplay the form at the original URL?

/item/10101

(I’ve tried getting the referrer and redirecting to it in processForm but then all of the model contents end up displayed as URL name/value pairs:)

@RequestMapping(value = "/process_form", method = RequestMethod.POST)
public final String processForm(HttpServletRequest request,
 @ModelAttribute("foo") FooModel fooModel,
    BindingResult bindResult,
    ModelMap model)
{
    String referrer = request.getHeader("referer");

    FooModelValidator validator = new FooModelValidator();
    validator.validate(FooModel, bindResult);

      if (bindResult.hasErrors())
      {
        model = this.fillModel(fooModel.getItemId());
       return "redirect:" + referrer;
      }
    return "account";
}

Answer 1

Short answer: No.

What happens is a server-side redirect (forward), which is within the same request, and so the submitted values are preserved (and displayed in the form)

The url will change if you use a client-side redirect (return "redirect:item";), but in that case a new request will come and the submitted values will be lost.

But here are two options that you have:

• use the same URL in the mappings for both methods and distinguish them based on request method – GET for the former, POST for the latter. This might be confusing, so document it.

• find / implement flash scope for spring-mvc. There’s nothing built-in. The flash scope means that values are preserved (in the session usually) for a submit and the subsequent redirect. This option includes the manual handling, by putting the submitted object in the session, and later retrieving & removing it