SpringBoot_05_ssm拦截器和默认欢迎页面的设置

1.在springBoot下通过使用拦截器完成在没有登陆的前提下，不允许访问其他资源

编写拦截器，要实现HandlerInterceptor

@Component
public class UserInterceptor implements HandlerInterceptor {

    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        HttpSession session = request.getSession();
        //这里的User是登陆时放入session的
        Users user = (Users) session.getAttribute("user");
        if (user == null){
             request.getRequestDispatcher("/login.jsp").forward(request, response);
            return false;
        }else {
            return true;    //如果session里有user，表示该用户已经登陆，放行，用户即可继续调用自己需要的接口
        }
    }

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

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

    }

}

2.在和启动类同一层编写配置类同时可以设置默认的欢迎页面

@SpringBootConfiguration
public class SpringMvcConfigure implements WebMvcConfigurer
{
    @Autowired
    public UserInterceptor userInterceptor;

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

}

<你是我自罚三杯也不肯开口的秘密>