Spring（十）——使用注解实现AOP

【纯注解方式比较麻烦，仅仅适用于个别方法配置，大面积方法配置需要结合xml】

配置applicationContext.xml
【注意】Spring不会自动寻找注解，需要引入新的命名空间——xmlns:context（多个包需要用逗号分割）来配置注解在那些包中

<?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"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">
	<!--配置需要添加注解的包-->
	<context:component-scan base-package="com.ouc.advice,com.ouc.demo"></context:component-scan>	
	
	<!--proxy-target-class
		true 使用cglib动态代理
		false 使用jdk动态代理
	-->
	<aop:aspectj-autoproxy proxy-target-class="true"></aop:aspectj-autoproxy>
</beans>

在Demo类中添加@Componet
（1）@Componet
　　① 相当于<bean/>
　　② 如果没有参数，把类名首字母变小写（如demo）,相当于<bean/>的id
　　③ 也可以自定义id，@Componet(“自定义名称”)　　
（2）＠Pointcut(" ")定义切点

package com.ouc.demo;

import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;

@Component
public class Demo {
	@Pointcut("execution(* com.ouc.demo.Demo.demo1())")
	public void demo1(){
		//int i =5/0;
		System.out.println("demo1");		
	}
}

在通知类中配置
（1）@Componet类被Spring管理
（2）@Aspect相当于<aop:aspect/>，表示通知方法在当前类

package com.ouc.advice;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.springframework.stereotype.Component;

@Component
@Aspect
public class MyAdvice {
	@Before("com.ouc.demo.Demo.demo1()")
	public void mybefore(){
		System.out.println("前置");
	}
	@After("com.ouc.demo.Demo.demo1()")
	public void myafter(){
		System.out.println("后置");
	}
/*	@AfterThrowing("com.ouc.demo.Demo.demo1()")
	public void mythrow(){
		System.out.println("异常");
	}*/
	@Around("com.ouc.demo.Demo.demo1()")
	public Object myarround(ProceedingJoinPoint p) throws Throwable{
		System.out.println("执行环绕");
		System.out.println("环绕-前置");
		Object result = p.proceed();
		System.out.println("环绕-后置");
		return result;
	}
}

测试类

package com.ouc.test;

import java.util.Arrays;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;


import com.ouc.demo.Demo;

public class Test {
	public static void main(String[] args) throws Exception {
		ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml");
		String[] list = ac.getBeanDefinitionNames();
		System.out.println(Arrays.toString(list));
		Demo demo = ac.getBean("demo", Demo.class);
		demo.demo1();
	}
}

结果

来源：CSDN

作者：Heart of Ocean

链接：https://blog.csdn.net/weixin_43180675/article/details/103733742

标签

aop

xmlns

schema

context