前文已经讨论了基于配置文件方式实现Spring AOP（Spring AOP - 配置文件方式实现），本文采用注解的方式实现前文相同的功能。配置步骤如下：

        1、项目增加aop依赖（pom.xml)

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.2.20.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.6</version>
        </dependency>

         2、配置文件增加注解扫描的包（applicationContext.xml）

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns="http://www.springframework.org/schema/beans"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd">
    <!-- 扫描com.text包及子包下的注解-->
    <context:component-scan base-package="com.text"/>
</beans>

        3、增加切面类（开启切面注解@EnableAspectJAutoProxy、增加切面标识@Aspect）及通知方法（环绕通知@Around，并配置切点表达式execution）

package com.text.aspect;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
import org.springframework.stereotype.Component;
import java.util.Date;

/**
 * 定义方法切面类
 */
@EnableAspectJAutoProxy //开启AspectJ的注解方式
@Component
@Aspect //标识为切面类
public class MethodAspect {
    //配置环绕通知
    @Around("execution(public * com.text..*DaoImpl.*(..))")
    public void countMethodInvokeTime(ProceedingJoinPoint proceedingJoinPoint) {
        System.out.println("目标方法执行之前记录初始时间...");
        Date startTime = new Date();
        try {
            proceedingJoinPoint.proceed();//执行目标方法 即：StudentDaoImpl.getById方法
            System.out.println("目标方法执行之后记录结束时间...");
            String methodName = proceedingJoinPoint.getTarget().getClass().getName() + "." +
                    proceedingJoinPoint.getSignature().getName();
            Date endTime = new Date();
            System.out.println(methodName + "方法执行总时长为：" + (endTime.getTime() - startTime.getTime()) + "毫秒");
        } catch (Throwable throwable) {
            throwable.printStackTrace();
        }
    }
}

        4、业务方法StudentDaoImpl

package com.text.dao.impl;
import com.text.dao.StudentDao;
import org.springframework.stereotype.Repository;

@Repository
public class StudentDaoImpl implements StudentDao {
    @Override
    public void getById(String id) throws Exception {
        Thread.sleep(1000);
        System.out.println("查询学生id=" + id + "的信息");
    }
}

         5、测试类Application

package com.text;

import com.text.dao.StudentDao;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Application {
    public static void main(String[] args) throws Exception {
        ApplicationContext context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
        StudentDao studentDao = context.getBean("studentDaoImpl", StudentDao.class);
        studentDao.getById("1");
        System.out.println("======getById end ========");
    }
}

        6、程序运行结果