拦截器可以获取IOC容器中的各个bean,拦截器是基于java的反射机制的,拦截器只能对action请求起作用,拦截器可以访问action上下文、值栈里的对象，但无法获取参数。

一、实现HandlerInterceptor接口

package com.wt.cloud.filter;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Slf4j
@Component
public class MyInterceptor implements HandlerInterceptor{

    /**
     * 功能描述: 执行方法前
     * @return : boolean
     * @author : big uncle
     * @date : 2019/10/9 12:24
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        log.info("执行方法前");
        return false;
    }

    /**
     * 功能描述: 执行方法后，有异常不执行
     * @return : boolean
     * @author : big uncle
     * @date : 2019/10/9 12:24
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        log.info("执行方法后，有异常不执行");
    }

    /**
     * 功能描述: 执行完一定会执行
     * @return : boolean
     * @author : big uncle
     * @date : 2019/10/9 12:24
     */
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        log.info("执行完一定会执行");
    }
}

二、注册到InterceptorRegistration

package com.wt.cloud.config;

import com.wt.cloud.filter.MyInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;


@Configuration
public class InterceptorConfig implements WebMvcConfigurer{

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //註冊TestInterceptor拦截器 new 或者 注入 都行
        InterceptorRegistration registration = registry.addInterceptor(new MyInterceptor());
        //所有路径都被拦截
        registration.addPathPatterns("/**");
        //添加不拦截路径
        registration.excludePathPatterns("/","/error","/static/**");
    }
}