spring学习笔记四:AOP

时间:2021-10-06 10:01:48

AOP(Aspect Orient Programming),面向切面编程,是对面向对象编程OOP的一种补充

面向对象编程使用静态角度考虑程序的结构,而面向切面编程是从动态角度考虑程序运行过程

AOP底层,就是采用动态代理模式实现的。采用了两种代理:JDK的动态代理域CGLIB的动态代理

 

AOP编程属于:

1.切面(Aspect)

切面泛指交叉业务逻辑

 

2.织入(weaving)

织入是指将切面代码插入到目标对象的过程

 

3.切入点(Pointcut)

切入点指切面具体织入的位置

 

4.目标对象(Target)

目标对象指将要被增强的对象

 

5.通知(Advice)

通知是切面的一种具体实现,可以完成简单织入功能

 

6.顾问(Advisor)

顾问是切面的另一种实现,能够将通知以更为复杂的方式织入到目标对象中,是将通知包装为更复制切面的装配器

 

spring学习笔记四:AOP

 

 

 

Spring的AOP编程环境搭建

1.创建Maven项目,配置spring的AOP需要的jar包

 spring学习笔记四:AOP

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>SrpingTest</groupId>
<artifactId>SrpingTest</artifactId>
<version>0.0.1-SNAPSHOT</version>
<build>
<sourceDirectory>src</sourceDirectory>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.6.1</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>4.3.8.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.3.2.RELEASE</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjrt</artifactId>
<version>1.8.2</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.8.2</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>4.3.2.RELEASE</version>
</dependency>
</dependencies>
</project>

 

2.创建接口UserService.java

spring学习笔记四:AOP

package com.agent.service;

public interface UserService {

void addUser(String name, String password);

}

 

3.创建实现类UserServiceImpl.java

package com.agent.service.impl;

import org.springframework.stereotype.Service;

import com.agent.service.UserService;

@Service(value
="userService")
public class UserServiceImpl implements UserService {

@Override
public void addUser(String name, String password) {
System.out.println(
"UserServiceImpl.addUser()...... name: " + name + "; password: " + password);
}

}

 

4.创建AOP的实现,用来记录日志,在方法执行时,记录下方法名和参数的日志工具,LogUtil.java

package com.agent.aop;

import org.aspectj.lang.JoinPoint;

public class LogUtil {

public void logWrited(JoinPoint point) {

StringBuffer sb
= new StringBuffer();
sb.append(
"记录日志--> 执行方法: " + point.getSignature().getName() + "; 传入参数: [");
// sb.append("记录日志--> 执行方法: " + point.getSignature().getDeclaringType() + "; 传入参数: [");
// sb.append("记录日志--> 执行方法: " + point.getSignature().getDeclaringTypeName() + "; 传入参数: [");

Object[] objectArray
= point.getArgs();
for(int i=0; i<objectArray.length; i++) {
if(objectArray[i] instanceof String) {
sb.append(String.valueOf(objectArray[i])).append(
", ");
}
}

sb.append(
"]");
System.out.println(sb.toString());
}


}

 

5.配置spring的配置文件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"
xsi:schemaLocation
="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx.xsd"
>

<context:component-scan base-package="com.agent" />

<bean id="aspect" class="com.agent.aop.LogUtil" />
<aop:config>
<aop:aspect ref="aspect">
<aop:pointcut expression="execution(* add*(..))" id="mypointcut"/>
<aop:after method="logWrited" pointcut-ref="mypointcut"/>
</aop:aspect>
</aop:config>
</beans>

 

6.创建测试方法AOPTest.java

package com.agent.test;

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

import com.agent.service.UserService;

public class AOPTest {

public static void main(String[] args) {

ApplicationContext ac
= new ClassPathXmlApplicationContext("applicationContext.xml");
UserService us
= (UserService)ac.getBean("userService");
us.addUser(
"张三", "188");
}

}

 

7.执行测试方法查看结果:

spring学习笔记四:AOP