Java框架spring 学习笔记（十四）：注解aop操作

回见Java框架spring Boot学习笔记（十三）：aop实例操作，这里介绍注解aop操作

首先编写一个切入点HelloWorld.java

package com.example.spring;

public class HelloWorld {
    public void printHello(){
        System.out.println("Hello Aop.");
    }
}

 编写切面TimeHandler.java

package com.example.spring;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;

//使用@Aspect注解轻松定义切面
@Aspect
public class TimeHandler {

    // 在方法上面使用注解完成前置增强配置
    @Before(value = "execution(* com.example.spring.HelloWorld.*(..))")
    public void beforTime()
    {
        System.out.println("前置增强：CurrentTime = " + System.currentTimeMillis());
    }

    // 在方法上面使用注解完成后置增强配置
    @After(value = "execution(* com.example.spring.HelloWorld.*(..))")
    public void afterTime()
    {
        System.out.println("后置增强：CurrentTime = " + System.currentTimeMillis());
    }

    // 在方法上面使用注解完成环绕增强配置
    @Around(value = "execution(* com.example.spring.HelloWorld.*(..))")
    public void aroundTime(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
        //方法之前
        System.out.println("环绕增强：CurrentTime = " + System.currentTimeMillis());

        //执行被增强的方法
        proceedingJoinPoint.proceed();

        //方法之后
        System.out.println("环绕增强：CurrentTime = " + System.currentTimeMillis());
    }
}

 编写配置文件aop.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop-4.2.xsd">

    <!-- bean definition & AOP specific configuration -->
    <!-- 1 配置对象-->
    <bean id="helloWorld" class="com.example.spring.HelloWorld"/>
    <bean id="timeHandler" class="com.example.spring.TimeHandler"/>

    <!-- 2 开启aop操作-->
    <aop:aspectj-autoproxy></aop:aspectj-autoproxy>

</beans>

编写运行文件Application.java

package com.example.spring;

import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Application {
    public static void main(String[] args) {
        //bean配置文件所在位置 D:\\IdeaProjects\\spring\\src\\Beans.xml
        //使用AbstractApplicationContext容器
        AbstractApplicationContext context = new ClassPathXmlApplicationContext("file:D:\\IdeaProjects\\spring\\src\\aop.xml");
        //得到配置创建的对象
        HelloWorld helloWorld = (HelloWorld)context.getBean("helloWorld");
        helloWorld.printHello();
    }
}

运行输出

环绕增强：CurrentTime = 1510208830742
前置增强：CurrentTime = 1510208830742
Hello Aop.
环绕增强：CurrentTime = 1510208830750
后置增强：CurrentTime = 1510208830750