java - Spring MVC 中重定向时丢失 @SessionAttribute

Question

我面临着一个特殊的问题。我正在学习 SpringMVC，这是我第一个使用它的应用程序项目。

当我们在 Controller 中使用@SessionAttributes注释时，如果调用任何具有与其签名中的@SessionAttribute同名的@ModelAttribute参数的处理程序方法，则 session 属性会自动更新。

现在我将控件重定向到另一个处理程序方法，该方法又呈现一个 jsp。我面临的问题是我能够在重定向处理程序方法中访问 @SessionAttribute 但在 jsp 中它呈现 session 属性丢失。

这是代码。

@Controller
@EnableWebMvc
@RequestMapping("/courtreservation/*")
@SessionAttributes("courtDetails")
public class ControllerServlet {



@RequestMapping(value="basePage",method=RequestMethod.GET)
public String basePageRenderer(Model model,HttpServletRequest request){
CourtDetails tempObj = (CourtDetails)request.getSession().getAttribute("courtDetails");        
 GenericXmlApplicationContext context = new GenericXmlApplicationContext();
    context.load("configs/applicationContext.xml");
    context.refresh();
    CourtDetails courtDetails = (CourtDetails)context.getBean("courtDetails");
    List<String> allSports = courtDetails.getAllSports();
    Calendar calendar = Calendar.getInstance();
    int numDay = calendar.get(Calendar.DAY_OF_WEEK);
    System.out.println(numDay);
    String[] days = {"sunday","monday","tuesday","wednesday","friday","saturday","sunday"};
    /*List<String> daysAvailableForReservation = new ArrayList<>();
    if(numDay == 1) {
        for(String day:days) {
            daysAvailableForReservation.add(day);
        }
    }
    else {
       for(int i=numDay--;i<days.length;i++) {
           daysAvailableForReservation.add(days[i]);
       }
    }*/
    model.addAttribute("daysAvailableForReservation", days);
    model.addAttribute("courtDetails", courtDetails);
    model.addAttribute("allSports",allSports);
    return "welcomePage";
}

@RequestMapping(value="checkAvailability",method=RequestMethod.POST)
public String checkAvailability(CourtDetails courtDetails,HttpServletRequest request,HttpServletResponse response,Model model) {
    HttpSession session = request.getSession();
    courtDetails = (CourtDetails)session.getAttribute("courtDetails");
    Boolean isAvailable = courtDetails.checkAvailability();
    if(isAvailable) {
        model.addAttribute("isAvailable","true");
        model.addAttribute("courtDetails",courtDetails);
        return "welcomePage";
    }
    model.addAttribute("isAvailable", "false");
    model.addAttribute("courtDetails",courtDetails);
    return "unavailable";
}






}

从 checkAvailability 重定向后，@SessionAttribute("courtDetails") 在 basePageRenderer() 中可用，但在它呈现的 jsp(welcomePage.jsp)中不可用。

这是 View 分辨率配置。

1) Controller servlet 配置:

<bean class="org.springframework.web.servlet.view.XmlViewResolver" 
          p:location="/WEB-INF/classes/configs/appViews.xml" 
          p:order="0" />

2) appView.xml

<bean id="unavailable"
      class="org.springframework.web.servlet.view.RedirectView"
      p:url="/Sports_Reservation/courtreservation/basePage"  />

Answer 1

似乎解释得很好here 。我遇到了类似的问题，最终使用 forward 而不是 redirect。