Spring MVC：重定向後顯示驗證消息

我有一些非常奇怪的問題，顯示重定向後的錯誤消息。我使用RedirectAttributes將帶有錯誤消息的BindingResult對象傳遞給視圖，但此解決方案不起作用。Spring MVC：重定向後顯示驗證消息

當我只返回一個視圖名稱與重定向，一切工作正常。

有人可以給出建議，但沒有會話使用？

@Controller 
public class UserRegistrationController { 

    @Autowired 
    private UserService userService; 

    @RequestMapping(value="/registration", method=RequestMethod.GET) 
    public ModelAndView registrationPage() { 
     ModelAndView modelAndView = new ModelAndView("user-registration/registration-form"); 
     modelAndView.addObject("user", new User()); 
     return modelAndView; 
    } 

    @RequestMapping(value="/registration", method=RequestMethod.POST) 
    public ModelAndView registerUser(@ModelAttribute @Valid User user, 
      BindingResult result, 
      final RedirectAttributes redirectAttributes) { 
     ModelAndView modelAndView = new ModelAndView("redirect:registration.html"); 

     User tempUser = userService.get(user.getEmail()); 
     Map<String, String> messages = new HashMap<String, String>(); 

     if (tempUser == null && ! result.hasErrors()) { 
      userService.save(user); 
      messages.put("success", "message.user.success.register"); 
     } else { 
      messages.put("error", "message.user.invalid.register"); 
      redirectAttributes.addFlashAttribute("user", user); 
      redirectAttributes.addFlashAttribute("errors", result); 
     } 

     redirectAttributes.addFlashAttribute("messages", messages); 

     return modelAndView; 

    } 

}

和視圖代碼：

<p> 

    <c:forEach var="message" items="${messages}"> 
     <span class="${message.key}"><spring:message code="${message.value}" /></span><br /> 
    </c:forEach> 

</p> 

<form:form method="POST" commandName="user" action="${pageContext.request.contextPath}/registration.html"> 
<table> 
<tbody> 
    <tr> 
     <td><spring:message code="user.registration.email" /></td> 
     <td><form:input path="email" /></td> 
     <td><form:errors cssClass="error" path="email" /></td> 
    </tr> 
    <tr> 
     <td><spring:message code="user.registration.password" /></td> 
     <td><form:password path="password" /></td> 
     <td><form:errors cssClass="error" path="password" /></td> 
    </tr> 
    <tr> 
     <td><input type="submit" /></td> 
     <td></td> 
     <td></td> 
    </tr> 
</tbody> 
</table> 
</form:form>

來源

2013-06-28 Alex Fruzenshtein