1.先创建一般的Controller实体类
UserController.java

package com;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
@RequestMapping("/user")
public class UserController {
    @RequestMapping("/testInterceptor")
    public String testInterceptor(){
        System.out.println("testInterceptor执行了...");
        return "success";
    }
}

2.编写index.jsp

<%--
  Created by IntelliJ IDEA.
  User: My
  Date: 2021/2/13
  Time: 8:53
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<script src="js/jquery.min.js"></script>


<body>

<h3>拦截器</h3>

<a href="user/testInterceptor">拦截器</a>

</body>
</html>

3.拦截器编写 第一步：编写一个普通类实现 HandlerInterceptor 接口

MyInterceptor1.java

package com;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

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

public class MyInterceptor1 implements HandlerInterceptor {
    /**
     * 预处理，controller方法执行前
     * return true 放行，执行下一个拦截器，如果没有，执行controller中的方法
     * return false不放行
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("MyInterceptor1执行了...前1111");
        // request.getRequestDispatcher("/WEB-INF/pages/error.jsp").forward(request,response);
        return true;
    }

    /**
     * 后处理方法，controller方法执行后，success.jsp执行之前
     * @param request
     * @param response
     * @param handler
     * @param modelAndView
     * @throws Exception
     */
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("MyInterceptor1执行了...后1111");
        // request.getRequestDispatcher("/WEB-INF/pages/error.jsp").forward(request,response);
    }

    /**
     * success.jsp页面执行后，该方法会执行
     * @param request
     * @param response
     * @param handler
     * @param ex
     * @throws Exception
     */
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("MyInterceptor1执行了...最后1111");
    }

}

第二步：配置拦截器

在springmvc.xml中配置

<!--配置拦截器-->
    <mvc:interceptors>
        <!--配置拦截器-->
        <mvc:interceptor>
            <!--要拦截的具体的方法-->
            <mvc:mapping path="/user/*"/>
            <!--不要拦截的方法
            <mvc:exclude-mapping path=""/>
            -->
            <!--配置拦截器对象-->
            <bean class="com.MyInterceptor1" />
        </mvc:interceptor>
    </mvc:interceptors>

测试运行结果：

SpringMVC中自定义拦截器的步骤_spring

总结:

preHandle 方法              预处理，controller方法执行前
postHandle 方法            后处理方法，controller方法执行后，success.jsp执行之前
afterCompletion 方法     success.jsp页面执行后，该方法会执行