使用Spring的注解方式实现AOP

作者：Bird

Spring对AOP的实现提供了很好的支持。下面我们就使用Spring的注解来完成AOP做一个例子。

首先，为了使用Spring的AOP注解功能，必须导入如下几个包。aspectjrt.jar,aspectjweaver.jar,cglib-nodep.jar.

然后我们写一个接口

package com.bird.service;

public interface PersonServer {

    public void save(String name);
    public void update(String name, Integer id);
    public String getPersonName(Integer id);
    
}

和一个接口实现类

package com.bird.service.impl;

import com.bird.service.PersonServer;

public class PersonServiceBean implements PersonServer{
    
    @Override
    public void save(String name) {
        
        System.out.println("我是save方法");
    //    throw new RuntimeException();
    }

    @Override
    public void update(String name, Integer id) {
        
        System.out.println("我是update()方法");
    }

    @Override
    public String getPersonName(Integer id) {
        
        System.out.println("我是getPersonName()方法");
        return "xxx";
    }

}

下面使用Spring注解方式对这个Bean进行方法拦截

package com.bird.service;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.AfterReturning;
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.aspectj.lang.annotation.Pointcut;

/**
 * 切面
 * @author Bird
 *
 */
@Aspect
public class MyInterceptor {
    @Pointcut("execution(* com.bird.service.impl.PersonServiceBean.*(..))")
    private void anyMethod(){}//定义一个切入点
    
    @Before("anyMethod() && args(name)")
    public void doAccessCheck(String name){
        System.out.println(name);
        System.out.println("前置通知");
    }
    
    @AfterReturning("anyMethod()")
    public void doAfter(){
        System.out.println("后置通知");
    }
    
    @After("anyMethod()")
    public void after(){
        System.out.println("最终通知");
    }
    
    @AfterThrowing("anyMethod()")
    public void doAfterThrow(){
        System.out.println("例外通知");
    }
    
    @Around("anyMethod()")
    public Object doBasicProfiling(ProceedingJoinPoint pjp) throws Throwable{
        System.out.println("进入环绕通知");
        Object object = pjp.proceed();//执行该方法
        System.out.println("退出方法");
        return object;
    }
}
@Pointcut("execution(* com.bird.service.impl.PersonServiceBean.*(..))")

这句话是方法切入点，execution为执行的意思，*代表任意返回值，然后是包名，.*意思是包下面的所有子包。(..)代

表各种方法.

然后下面的注解就比较简单了，就是在使用方法前和中，还有环绕拦截/

然后在Spring的配置文件中继续配置Bean,需要打开AOP命名空间

<?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-2.5.xsd
       http://www.springframework.org/schema/aop 
       http://www.springframework.org/schema/aop/spring-aop-2.5.xsd">
        
        <aop:aspectj-autoproxy/>
    <bean id="personServiceBean" class="com.bird.service.impl.PersonServiceBean"/>
    <bean id="myInterceptor" class="com.bird.service.MyInterceptor"/>
   
</beans>

然后建立一个Junit测试

package junit.test;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.bird.service.PersonServer;

public class SpringAOPTest {
    
    @Test
    public void inteceptorTest(){
        ApplicationContext ctx = new ClassPathXmlApplicationContext("beanAop.xml");
        PersonServer bean = (PersonServer)ctx.getBean("personServiceBean");
        bean.save(null);
    }
    

}

测试结果为

2012-3-12 18:08:39 org.springframework.context.support.AbstractApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@dd20f6: display name [org.springframework.context.support.ClassPathXmlApplicationContext@dd20f6]; startup date [Mon Mar 12 18:08:39 CST 2012]; root of context hierarchy
2012-3-12 18:08:40 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [beanAop.xml]
2012-3-12 18:08:40 org.springframework.context.support.AbstractApplicationContext obtainFreshBeanFactory
信息: Bean factory for application context [org.springframework.context.support.ClassPathXmlApplicationContext@dd20f6]: org.springframework.beans.factory.support.DefaultListableBeanFactory@b0bad7
2012-3-12 18:08:40 org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons
信息: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@b0bad7: defining beans [org.springframework.aop.config.internalAutoProxyCreator,personServiceBean,myInterceptor]; root of factory hierarchy
null
前置通知
进入环绕通知
我是save方法
后置通知
退出方法
最终通知