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