Spring 3 HandlerInterceptor 将信息传递给控制器

Question

我已经设置了一个 Spring HandlerInterceptor 来向 HttpServletRequest 添加一个属性，以便能够从 Controller 中读取它，遗憾的是这似乎不起作用，这对我来说似乎很奇怪。我做错了吗？知道如何将数据从拦截器传输到控制器吗？

这是两个受影响类的简化代码

public class RequestInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {
        request.setAttribute("my-role", "superman");
    }
   [...]
}

@RestController
@RequestMapping("Test")
public class TestController {
    public final Logger logger = LoggerFactory.getLogger(getClass());

    @RequestMapping(value = "something")
    public void something(HttpServletRequest request) {
        logger.info(request.getAttribute("my-role"));
    }

    [...]
}

request.getAttribute("my-role") 返回 null...但是如果我在 HandlerInterceptor 的 postHandle 中读取它确实返回异常值，我觉得我错过了一些东西...

编辑：我发现使用“request.getSession().setAttribute”进行会话很有魅力，但我仍然不明白为什么请求本身在这个用例中不起作用。

Answer 1

您可以尝试使用会话而不是请求，如下所示。

  public boolean preHandle(HttpServletRequest request,
                HttpServletResponse response, Object handler) throws Exception {
                ...
                HttpSession session = request.getSession();
                session.setAttribute("attributeName", objectYouWantToPassToHandler);
                ....
                }
    In your handler handleRequest method:

       public ModelAndView handleRequest(HttpServletRequest request,
            HttpServletResponse response) throws Exception {                

            ....
            HttpSession session = request.getSession();
            objectYouWantToPassToHandler objectYouWantToPassToHandler = session.getAttribute("attributeName");
            ....


  }