spring AOP 返回后通知 简单示例

开始前我们要导入spring需要的jar包；

还需要引入 aspectjweaver.jar 和 cglib.jar 这两个jar包

如果是maven项目的话，在pom.xml 的dependencies节点下添加如下引用即可：

 

 

<dependency>

<groupId>aspectj</groupId>

<artifactId>aspectjweaver</artifactId>

<version>1.5.3</version>

</dependency>

<dependency>

<groupId>cglib</groupId>

<artifactId>cglib</artifactId>

<version>2.2.2</version>

</dependency>

现在开始：

 

首先，我们定义一个工程中要用到的简单实体Bean-- User.java

 

package org.xmy.ldq.entity;
import java.io.Serializable;
/**
 * 测试用实体
 * @author LiDuanqiang
 */
public class User implements Serializable{
	private static final long serialVersionUID = 5752197085695030514L;
	
	private String id;
	private String name;
	private String password;
	private String address;
	
	public User() {}
	public User(String id, String name,String password,String address) {
		super();
		this.id = id;
		this.name = name;
		this.password = password;
		this.address = address;
	}
	public String getId() {
		return id;
	}
	public void setId(String id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	
}

 

 接下来定义一个通知对象：UserAdvice.java

 

package org.xmy.ldq.aop;

import org.aspectj.lang.JoinPoint;

/**
 * 用户操作的通知对象
 * @author LiDuanqiang
 */
public class UserAdvice {
	/**
	 * 主体方法返回后将执行的通知方法
	 * @param JoinPoint 
	 * @param retValue主体方法传递到通知方法的返回值
	 * @return
	 */
	public Object afterReturning(JoinPoint joinPoint,Object retValue)throws Throwable{
		Object object = null;
		object = joinPoint.getThis();//返回代理对象
		/*切入点主体方法的名字*/
		String methodName = joinPoint.getSignature().getName();
		if (retValue instanceof Boolean && (Boolean)retValue && methodName.equals("login")) {
			System.out.println("方法:"+methodName+"()"+"成功执行;"+"登录成功!");
		}
		return object;
	}
}

 

 再定义一个目标类:AOPBean.java

 

package org.xmy.ldq;

import org.xmy.ldq.entity.User;


/**
 * 主体Bean
 * @author LiDuanqiang
 */
public class AOPBean{
	public Boolean login(User user){
		Boolean ret = false;
		/*用户名和密码都为ldq则成功登录*/
		if (user.getName().equals("ldq")&&user.getPassword().equals("ldq")) {
			ret = true;
		}
		return ret;
	}
	
}

 

 最后定义一个测试主程序的实现类：App.java

 

package org.xmy.ldq;

import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.xmy.ldq.entity.User;

/**
 * 测试
 * @author LiDuanqiang
 */
public class App{
	public static void main( String[] args ){
		ClassPathXmlApplicationContext factory =
			new ClassPathXmlApplicationContext("applicationContext.xml");
		AOPBean aopBean = (AOPBean) factory.getBean("aopBean");
		aopBean.login(new User("1","ldq","ldq","cs"));
		System.exit(0);
	}
}

 

 配置文件很重要:applicationContext.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:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:p="http://www.springframework.org/schema/p"
	xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
           http://www.springframework.org/schema/context
           http://www.springframework.org/schema/context/spring-context-2.5.xsd
           http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
           http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">
	<aop:config>
		<!-- 定义切点 -->
		<aop:pointcut id="login_PointcutTarget"  expression="execution(* org.xmy.ldq.AOPBean.login(..))"/>
		<!-- 定义切面 -->
		<aop:aspect id="userAspect" ref="userAdvice">
			<aop:after-returning
			pointcut-ref="login_PointcutTarget"
			arg-names="joinPoint,retValue"
			returning="retValue"
			method="afterReturning"
			/>
		</aop:aspect>
	</aop:config>
	
	<bean id="userAdvice" class="org.xmy.ldq.aop.UserAdvice"></bean>
	<bean id="aopBean" class="org.xmy.ldq.AOPBean"></bean>
	
</beans>

 

 说明：arg-names="joinPoint,retValue" 被切目标方法的参数名称；

 

returning="retValue" 目标方法成功执行后的返回值 一般类型定义为 Object；
method="afterReturning"目标方法名称

 

 

如果程序中报出

java.lang.NoClassDefFoundError: org/aspectj/weaver/reflect/ReflectionWorld$ReflectionWorldException

是aspectjweaver.jar包丢失了，将其引入即可；

 Cannot proxy target class because CGLIB2 is not available. Add CGLIB to the class path or specify proxy interfaces.错误 是因为采用的CGLIB代理，应把相应的jar包引入。