为何无法在普通类的静态方法中获取当前请求的HttpServletRequest对象？

Question

我想弄一个公用的getUser静态方法，这样就不用在每一个controller中都手动将token转成user了

public class UserUtil {
    @Autowired
    private static HttpServletRequest request;

    @Autowired
    private static HttpServletResponse response;

    public static User getUser() {
        return null;
    }

    public static String getUserName() {
        System.out.println(request);
        System.out.println(response);
        String cookieToken =CookieUtils.getCookie(request,"token");
        System.out.println("cookieToken:" + cookieToken);

        String headerToken = request.getHeader("token");
        System.out.println("headerToken:" + headerToken);
        return headerToken;
    }
}

可是这样并不能获取request对象，那应该怎么办呢？

Answer 1

谢谢邀请。

spring mvc在处理请求的时候，会把请求对象放到RequestContextHolder持有的ThreadLocal对象中,你可以去看看DispatcherServlet类的源代码。

//获取到当前线程绑定的请求对象
HttpServletRequest request = ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest();

Answer 2

@RestController
@RequestMapping("/api")
public class MyController {

    @Autowired
    private UserService userService;

    @GetMapping("/doSomething")
    public void doSomething(HttpServletRequest request) {
        String headerToken = request.getHeader("token");
    }
}