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的AOP编程环境搭建
1.创建Maven项目,配置spring的AOP需要的jar包
<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
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: