Proper way to set model errors in Spring Portlet MVC
===

In my MVC controller I have a handler method with a signature:

    public void myAction(ActionRequest request, ActionResponse response, Model model) {...}

And in this method I check if some submitted data is okay. If it's not valid, I want to set an error. Currently I do it this simple way:

    model.addAttribute("operationStatus", "error");
    model.addAttribute("operationMessage", "a lot of things went wrong");

and in the view JSP:

    <c:if test="${requestScope.operationStatus == 'error'}">
        <div class="msg-error">${requestScope.operationMessage}</div>
    </c:if>

Surely there has to be a better way to handle errors in Spring Portlet MVC. Note that I need to display the error messages in different places, not only in `<form>` tag.

So how should I handle errors?