how to display validation errors from another form submit - validation

Question

Imagine a form with a single field where the user provides their email. On POST, the controller action method sends a confirmation code to that email and displays a second form in which the user is supposed to enter the confirmation code they received. If the code does not match I then return the original view and I would like to display an error message next to the email ("email was not confirmed").
Sample code below:
1st view (asking the email)
<div>
Please provide the following information to sign-up:
<form:form modelAttribute="newAccountInfo" action="signup-submit.do" method="POST">
<div><form:label path="email">Email:</form:label>
<form:input type="text" path="email"/><form:errors path="email" cssClass="error" element="div"/>
</div>
...
1st view controller method
#RequestMapping(path="/signup-submit", method=RequestMethod.POST)
public String signupSubmit(HttpServletRequest request
, #ModelAttribute("newAccountInfo") #Valid NewAccountInfo newAccountInfo
, BindingResult result
, Model model) {
String confirmCode = generateRandomSecret();
// send confirmCode by email to newAccountInfo.email (omitted)
model.addAttribute("emailConfirmation" , new EmailConfirmation());
request.getSession().setAttribute("newAccountInfo", newAccountInfo);
request.getSession(false).setAttribute("email-code", confirmCode);
return View.SIGNUP_EMAIL_CONFIRMATION.name;
}
2nd view (asking the confirmation code)
<div>
Enter the confirmation code that was sent to your email:
<form:form modelAttribute="emailConfirmation" action="signup-email-confirmation-submit.do" method="POST">
<form:label path="code">Confirmation code:</form:label>
<form:input type="text" path="code"/>
<input type="submit" value="Submit" />
</form:form>
2nd view controller method
#RequestMapping(path="/signup-email-confirmation-submit", method=RequestMethod.POST)
public String signupEmailConfirmationSubmit(
#ModelAttribute("emailConfirmation") EmailConfirmation emailConfirmation
, BindingResult result
, Model model) {
if (emailConfirmation.getCode().equals(request.getSession(false).getAttribute("email-code")))
return View.SIGNUP_SUCCESS.name;
else {
model.addAttribute("newAccountInfo", request.getSession(false).getAttribute("newAccountInfo"));
request.getSession(false).invalidate();
// TODO - what should I do here ?
return View.SIGNUP.name;
}
Assuming the confirmation code was not correctly entered, what should I do in the second view controller method so that when the first view is displayed (for the second time), there is a field validation error message next to the email with description "email was not confirmed" ?
In the line marked with the TODO comment I 've tried the following:
result.rejectValue("email", null, "email was not confirmed");
… but that results in the following exception:
org.springframework.beans.NotReadablePropertyException: Invalid property 'email' of bean class [EmailConfirmation]: Bean property 'email' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?
(which makes sense as the email is not a field of EmailConfirmation).
However, the below also fails (silently, without an exception, the 1st view is displayed, I just don't see the validation error message):
result.addError(new FieldError("newAccountInfo", "email", "email could not be confirmed"));
In the end, the only way I could get this to work was to add a custom model property by adding the following (in the TODO line of the second view controller method always):
model.addAttribute("emailConfirmationError", true);
… and then modifying the 1st view as follows:
<div><form:label path="email">Email:</form:label>
<form:input type="text" path="email"/>
<form:errors path="email" cssClass="error" element="div"/>
<c:if test="${not empty emailConfirmationError}">
<span class="error">The email could not be confirmed</span>
</c:if>
</div>
The above succeeds but feels like a hack as I am not using the validation machinery of Spring MVC.
My questions are:
what is the idiomatic way to achieve the above
are there any other flawed mental models or misunderstandings present in the above code?