SpringMVC（七）：利用Cookie实现登陆验证

一、登陆时要往将用户登陆的信息存入Cookie

@RequestMapping("/doLogin")
    @ResponseBody
    public String doLogin(String userName, String userPassword, HttpServletResponse response) {
        User user = userService.queryUserByName(userName);
        if (user != null && user.getUserPassword().equals(userPassword)) {
            Cookie cookie = new Cookie(Constant.USERNAME, userName);
            cookie.setMaxAge(7*24*60*60);
            response.addCookie(cookie);
            return "true";
        }
        return "false";
    }

cookie.setMaxAge()是设置cookie的过期时间，这里设置的是7天过期，如果不进行时间设置，cookie默认会在浏览器关闭时过期。

二、拦截器中验证cookie

public class LoginInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        Cookie[] cookies = request.getCookies();
        if (cookies != null) {
            for (Cookie cookie : cookies) {
                if (cookie.getName().equals(Constant.USERNAME)) return true;
            }
        }
        response.sendRedirect("/login");
        return false;
    }
}

 三、进入登陆页面时判断cookie，若存在则无需登录，不存在则需要登录

@RequestMapping("/login")
    public String loginPage(HttpServletRequest request, String userName, Model model) {
        Cookie[] cookies = request.getCookies();
        if (cookies != null) {
            for (Cookie cookie : cookies) {
                if (Constant.USERNAME.equals(cookie.getName()))
                    return "redirect:/user/main";
            }
        }
        if (userName != null) model.addAttribute("userName", userName);
        return "login";
    }

四、注销时删除cookie

@RequestMapping("/doLogout")
    public String doLogout(HttpServletRequest request, HttpServletResponse response) {
        Cookie[] cookies = request.getCookies();
        if (cookies != null){
            for (Cookie cookie : cookies) {
                if (cookie.getName().equals(Constant.USERNAME)) {
                    cookie.setMaxAge(0);
                    cookie.setPath("/");
                    response.addCookie(cookie);
                }
            }
        }
        return "redirect:/";
    }

（本文仅作个人学习记录用，如有纰漏敬请指正）