SpringBoot通过拦截器拦截非登录用户

使用springmvc中的intercepter进行页面的拦截,拦截除了登录界面的所有页面,当用户登录过后产生保存用户信息的session。在拦截器通过判断session进行页面跳转。
1.登录页面html

    
    




    用户名
    

    密码
    
    

    

2.在自动配置类中配置需要拦截的页面和请求映射

@Configuration
public class MvcConfig implements WebMvcConfigurer {

    @Bean
     public WebMvcConfigurer  webMvcConfigurer(){
       return new WebMvcConfigurer(){
            @Override
            public void addInterceptors(InterceptorRegistry registry) {
                InterceptorRegistration interceptorRegistration = registry.addInterceptor(new InterceptLogin());
                /*拦截除了/ 和/index.html之外的全部请求*/
                interceptorRegistration.addPathPatterns("/**");
                interceptorRegistration.excludePathPatterns("/","/index.html");
            }

           @Override
           public void addViewControllers(ViewControllerRegistry registry) {
               registry.addViewController("/index.html").setViewName("index");
           }
       };
     }
}

3.拦截请求

public class InterceptLogin implements HandlerInterceptor  {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        HttpSession session = request.getSession();
        /*获取用户信息*/
        Object user = session.getAttribute("user");
        /*如果用户信息为空跳转到登录页面*/
        if(user==null){
            request.setAttribute("msg","请重新登录");
            request.getRequestDispatcher("index.html").forward(request, response);
            return false;
        }
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }
}

4.业务逻辑层

@Controller
public class UserController {

    @RequestMapping("/")
    public String userLogin(User user,HttpSession session){
        User user1 = (User) session.getAttribute("user");
        /*如果信息从登陆页面传入,session中存入用户信息*/
        if(user.getUsername()!=null){
            session.setAttribute("user", user);
            return "redirect:/user";
        }
        if(user1!=null){
            return "redirect:/user";
        }
        return "index";
    }
    @ResponseBody
    @RequestMapping("user")
    public String user(HttpSession session){
        User user = (User) session.getAttribute("user");
        return user.toString();
    }
}

user

public class User {
    private String username;
    private String password;
    getter..setter....
}

5.效果图
直接访问其他的url

用户登录后