Question

I have seen that I can add errors and render them via <form:errors /> tag and addError() method of BindingResult class, but I wonder if there is something similar to send information messages to the JSP.

I mean, I want to add messages when the operation has been successful. I know I could do it by sending an error, but it would make no sense to me to add errors when there haven’t been any error at all.

Answer 1

Interesting. I found this in an old project of mine.:

(this was a base controller, but could well be an utility method)

protected void addMessage(String key, boolean isError,
        HttpServletRequest request, Object... args) {
    List<Message> msgs = (List<Message>) request.getAttribute(MESSAGES_KEY);
    if (msgs == null) {
        msgs = new LinkedList<Message>();
    }

    Message msg = new Message();
    msg.setMessage(msg(key, args));
    msg.setError(isError);
    msgs.add(msg);
    request.setAttribute(MESSAGES_KEY, msgs);
}

and then in a messages.jsp which was included in all pages I had:

<c:forEach items="${messages}" var="message">
   //display messages here
</c:forEach>

MESSAGES_KEY is a constant of mine with a value “messages” (so that it is later accessible in the forEach loop).

The Message class is a simple POJO with those two properties. I used it for info messages as well as for custom non-validation errors.

This is a rather custom solution, but perhaps I hadn’t found a built-in solution then. Google a bit more before using such a solution.