RedirectView之后的Spring處理FlashAttributes

Question

我有一個頁面check ，我添加flashAttribute("error","Test message"); 並返回RedirectView進行頁面login 。

@RequestMapping(value = "/login")
public ModelAndView mainPage(Model model){

    System.out.println(" - " + model.asMap().get("error") + " - "); //-> - null -

    return new ModelAndView("/login");

}

@RequestMapping(value = "/check")
public View checkLogin(RedirectAttributes redirectAttributes,
                       @RequestHeader(value = "username", required = false)String username,
                       @RequestHeader(value = "password", required = false)String password){

    redirectAttributes.addFlashAttribute("error", "Test message");
    return new RedirectView("/login");

}

這行代碼： model.asMap().get("error")返回null 。 如何處理RedirectAttributes ？

Answer 1

我想這可能對您有幫助。

@RequestMapping(value = "/login")
public ModelAndView mainPage(RedirectAttributes redirectAttrs){
    Map<String> attributesMap = redirectAttrs.getFlashAttributes();

    return new ModelAndView("/login");

}

@RequestMapping(value = "/check")
public View checkLogin(RedirectAttributes redirectAttributes,
                       @RequestHeader(value = "username", required = false)String username,
                       @RequestHeader(value = "password", required = false)String password){

    redirectAttributes.addFlashAttribute("error", "Test message");
    return new RedirectView("/login");

}

希望這可以幫助