BindingResult argument only resolved right after model attribute argument [SPR-4753]

[spring-projects-issues]

Paul Middelkoop opened SPR-4753 and commented

Consider the following method signature:
@RequestMapping(params = "action=submitAndPreview", method = RequestMethod.POST)
public void submitAndPreview(
@SuppressWarnings("unused") @ModelAttribute(BasicController.ATTRIBUTE_ENTITY) Item item,
@ModelAttribute(ItemNodeController.ATTRIBUTE_NODE) ItemNode node,
@RequestParam("languageId") Integer languageId,
HttpSession session,
BindingResult result
Writer responseWriter) {

When calling thus methid I got the exception "java.lang.IllegalStateException: Errors/BindingResult argument declared without preceding model attribute. Check your handler method signature!"

After playing around with the method signature I noticed that the @RequestParam parameter results in this exception. When I remove this parameter or move it to the end of the parameter list it works.

---

Affects: 2.5.3

Issue Links:

• About @ModelAttribute, two commands, BindingResult [SPR-7358] #12016 About @ModelAttribute, two commands, BindingResult

[spring-projects-issues]

Juergen Hoeller commented

This is actually a known limitation: BindingResult arguments are at present only supported right after the corresponding model attribute. So in your case, the BindingResult refers to the ItemNode model attribute - and needs to follow right after that argument.

We may revise this a bit for Spring 3.0: maybe accepting a single BindingResult at any position provided that there's also only a single model argument in the signature. However, for multiple model arguments, the corresponding BindingResult arguments need to either explicitly specify the model attribute that they are referring to - or follow the positional convention.

Juergen

[spring-projects-issues]

Juergen Hoeller commented

We will keep this parameter alignment convention for the time being, since there's doesn't seem to be a strong need to change it.

Juergen

[spring-projects-issues]

Serge Kurenkov commented

@RequestMapping(value = "/tagDelete.do")
public String deleteTagAction(
        Model model,
        Errors errors,
        @RequestParam(value = "id", required = false) final String[] infoStrIds,
        HttpServletRequest request
        )

throws the same IllegalStateException("Errors/BindingResult argument declared without preceding model attribute. Check your handler method signature!");

I have model attibute in front of Errors and it still doesn't work.

[spring-projects-issues]

Juergen Hoeller commented

An Errors object exposes binding errors for a specific model attribute. Declaring the type Model doesn't help here since it exposes the entire model map, not a specific attribute.

You rather need to declare the concrete type that you're binding to, e.g. Account, and expect the subsequent Errors object to contain errors for that specific account instance (that current request parameters have been bound to).

Juergen