首先定义一个类：

ControllerInterceptor

内容如下：

public class ControllerInterceptor  implements HandlerInterceptor {
    private static final Logger log = LoggerFactory.getLogger(ControllerInterceptor.class);
    @Override
//这个方法是在进行控制器之前执行，可以在这里进行验证，我这里是进行对数据的请求进行jwt的验证，验证通过之后才可以进入控制器
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
                   Cookie[] cookies= httpServletRequest.getCookies();
                   if (cookies!=null){
                       for (Cookie cookie:cookies){
                           if (cookie.getName().equals("token")){
                               //说明拿到值了，进行token解密
                              JsonData jsonData= jwtutils.checkjwts(cookie.getValue());
                              if (jsonData.getCode()==200){
                                  //解密成功
                                  return true;
                              }
                           }
                       }
                   }
        return false;

    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
        log.info("--------------处理请求完成后视图渲染之前的处理操作---------------");
    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
        log.info("---------------视图渲染之后的操作-------------------------0");
    }



}

定义好这个拦截器之后我们需要让springboot知道我们有这个拦截器，所以我们需要定义一个类：

WebAppConfig

内容如下：

/**
 * function:让拦截器添加到springboot中
 */
@Configuration
public class WebAppConfig extends WebMvcConfigurerAdapter {
    @Override
    public void addInterceptors(InterceptorRegistry registry){
        registry.addInterceptor(new ControllerInterceptor()).addPathPatterns("/**").excludePathPatterns("/login/login1");
    }
}