springmvc request与response获取

request与response是Tomcat服务器在收到客户端请求后自己生成的，无需我们自己创建，但是在使用的时候可以有以下三种方式去获取

方法上直接使用，通过DispatcherServlet将参数传到MethodHandler直接使用

    @RequestMapping(path = {"/test10"}, method = RequestMethod.POST)
    @ResponseBody
    public BaseRes test10(HttpServletRequest request, HttpServletResponse response) {
        final HttpSession session = request.getSession();//创建session，如果没有则创建
        session.setAttribute("name","lisi");
        session.setAttribute("passwrod","123456");
        session.setAttribute();
        final Cookie cookie = new Cookie("name","wangwu");
        response.addCookie(cookie);//向浏览器返回cookie
        logger.info("session信息：{},sessionID:{}",session.getAttributeNames(),session.getId());
        final BaseRes success = BaseRes.success();
        success.setData(session.getAttributeNames());
        return success;
    }

RequestContextHolder，持有上下文的Request容器。可以用来获取当前请求信息以及响应信息，都是保存在ThreadLocal中，与线程绑定。

     @RequestMapping(path = {"/test13"}, method = RequestMethod.POST)
    @ResponseBody
    public BaseRes test13() {
        HttpServletRequest requests = ((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes()).getRequest();
        HttpServletResponse responses = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getResponse();
        final Cookie[] cookies = requests.getCookies();
        String value= "default";
        for (Cookie cookie:cookies){
            if (cookie.getName().equals("name")){
                value=cookie.getValue();
            }
        }
        final Cookie cookie = new Cookie("name","xxxxxx");
        responses.addCookie(cookie);//向浏览器返回cookie
        final BaseRes success = BaseRes.success();
        success.setData(value);
        return success;
    }

底层使用的RequestContextHolder，它在请求进来的时候进行注入，
参考：探讨 SpringMVC 能否注入 Request 和 Response

    @Autowired
    private HttpServletRequest request;
    @Autowired
    private HttpServletResponse response;
    @RequestMapping(path = {"/test12"}, method = RequestMethod.POST)
    @ResponseBody
    public BaseRes test12()  {
        final Cookie[] cookies = request.getCookies();
        String value= "default";
        for (Cookie cookie:cookies){
            if (cookie.getName().equals("name")){
                value=cookie.getValue();
            }
        }
        final Cookie cookie = new Cookie("name","dddd");
        this.response.addCookie(cookie);//向浏览器返回cookie
        final BaseRes success = BaseRes.success();
        success.setData(value);
        return success;
    }