1.Spring AOP简介
AOP (Aspect Oriented Programming)面向切面编程
OOP(Oriented Oriented Programming)面向对象编程
通过OOP的纵向和AOP的横向抽取,程序才可以真正解决问题
AOP的使用场景:日志 事务
2.AOP的核心概念
Aspect(切面)
Join Point(连接点)
Advice(通知/增强)
Pointcut(切点)
Introduction(引入)
Target Object(目标对象)
AOP Proxy(AOP代理)
Weaving(织入)
3.HelloWorld前置增强练习
给pom文件中添加aop依赖
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>{aspectj.version}</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>${aspectj.version}</version>
</dependency>
Hello接口类
package com.spring.aop;
public interface Hello {
String getHello();
}
HelloImpl类
package com.spring.aop;
public class HelloImpl implements Hello {
@Override
public String getHello() {
return "Hello,Spring AOP";
}
}
用户自定义的前置增强类MyBeforeAdvicelei
package com.spring.aop;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/*
- 用户自定义的前置增强类
-
/
public class MyBeforeAdvice {
private static final Logger logger= LoggerFactory.getLogger(MyBeforeAdvice.class);
/定义前置方法*/
public void beforeMethod() {
logger.info("This is a before method by wxy");
logger.debug("This is a before method by wxy");
//System.out.println("This is a before methoad");
}
}
用日志记录方法
配置文件
<!--配置一个Hello的bean 等同于Hello hello = new HelloImpl();-->
<bean id="hello" class="com.spring.HelloImpl"/>
<!--配置一个MyBeforeAdvice前置增强的bean-->
<bean id="mybeforeAdvice" class="com.spring.MyBeforeAdvice"/>
<!--配置Aop-->
<aop:config>
<aop:aspect id="before" ref="mybeforeAdvice">
<aop:pointcut id="myPointcut" expression="execution(* com.spring.aop.*.*(..))"/>
<aop:before method="beforeMethod" pointcut-ref="myPointcut"/>
</aop:aspect>
</aop:config>
HelloApp主类
package com.spring.aop;
import javafx.application.Application;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class HelloApp {
public static void main(String[] args) {
ApplicationContext context = new ClassPathXmlApplicationContext("/bean.xml");
Hello hello = context .getBean(Hello.class);
System.out.println(hello.getHello());
}
}