手动实现 Spring 底层机制实现任务阶段一编写自己 Spring 容器-准备篇【2】

😀前言
手动实现 Spring 底层机制的第2篇实现了任务阶段一编写自己 Spring 容器-准备篇【2】

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文章目录

😀手动实现 Spring 底层机制实现任务阶段一编写自己 Spring 容器-准备篇【2】
- 创建SmartAnimalable接口
- 创建SmartDog类
- 创建SmartAnimalAspect切面类
- 修改类beans.xml
- 创建AppMain类
- 输出结果
😄简单分析
- AOP 和 BeanPostProces关系
- 看一下 AnnotationAwareAspectJAutoProxyCreator 的类图
- 分析
- 😄总结

😀手动实现 Spring 底层机制实现任务阶段一编写自己 Spring 容器-准备篇【2】

创建SmartAnimalable接口

public interface SmartAnimalable {float getSum(float i, float j);float getSub(float i, float j);
}

创建SmartDog类

@Component
public class SmartDog implements SmartAnimalable {public float getSum(float i, float j) {float res = i + j;System.out.println("SmartDog-getSum-res=" + res);return res;}public float getSub(float i, float j) {float res = i - j;System.out.println("SmartDog-getSub-res=" + res);return res;}
}

创建SmartAnimalAspect切面类

@Component
@Aspect
public class SmartAnimalAspect {//给SmartDog配置前置，返回，异常，最终通知//前置通知@Before(value = "execution(public float com.wyxde.spring.aop.SmartDog.getSum(float, float))")public void showBeginLog(JoinPoint joinPoint) {//通过连接点对象joinPoint 可以获取方法签名Signature signature = joinPoint.getSignature();System.out.println("SmartAnimalAspect-切面类showBeginLog()[使用的myPointCut()]-方法执行前-日志-方法名-" + signature.getName() + "-参数 "+ Arrays.asList(joinPoint.getArgs()));}//返回通知@AfterReturning(value = "execution(public float com.wyxde.spring.aop.SmartDog.getSum(float, float))", returning = "res")public void showSuccessEndLog(JoinPoint joinPoint, Object res) {Signature signature = joinPoint.getSignature();System.out.println("SmartAnimalAspect-切面类showSuccessEndLog()-方法执行正常结束-日志-方法名-" + signature.getName() + " 返回的结果是=" + res);}//异常通知@AfterThrowing(value = "execution(public float com.wyxde.spring.aop.SmartDog.getSum(float, float))", throwing = "throwable")public void showExceptionLog(JoinPoint joinPoint, Throwable throwable) {Signature signature = joinPoint.getSignature();System.out.println("SmartAnimalAspect-切面类showExceptionLog()-方法执行异常-日志-方法名-" + signature.getName() + " 异常信息=" + throwable);}//最终通知@After(value = "execution(public float com.wyxde.spring.aop.SmartDog.getSum(float, float))")public void showFinallyEndLog(JoinPoint joinPoint) {Signature signature = joinPoint.getSignature();System.out.println("SmartAnimalAspect-切面类showFinallyEndLog()-方法最终执行完毕-日志-方法名-" + signature.getName());}}

修改类beans.xml

配置自动扫描的包, 同时引入对应的名称空间

如果我们是普通的java项目, beans.xml 放在src下
如果我们是java maven 项目, beans.xml 放在 src/main/resources

<?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"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop https://www.springframework.org/schema/aop/spring-aop.xsd"><context:component-scan base-package="com.wyxde.spring.component"/><context:component-scan base-package="com.wyxde.spring.aop"/><!--启用基于注解方式的AOP功能--><aop:aspectj-autoproxy/><!--配置后置处理器--><bean class="com.wyxde.spring.process.MyBeanPostProcessor" id="myBeanPostProcessor"/>
</beans>

创建AppMain类

public class AppMain {public static void main(String[] args) {//测试看看是否可以得到spring容器中的bean , 同时看看依赖注入是否OKApplicationContext ioc =new ClassPathXmlApplicationContext("beans.xml");UserAction userAction = (UserAction) ioc.getBean("userAction");UserAction userAction2 = (UserAction) ioc.getBean("userAction");System.out.println("userAction=" + userAction);System.out.println("userAction2=" + userAction2);UserDao userDao = (UserDao) ioc.getBean("userDao");System.out.println("userDao=" + userDao);UserService userService = (UserService) ioc.getBean("userService");System.out.println("userService=" + userService);//测试一下当前的依赖注入userService.m1();//测试一下AOPSmartAnimalable smartDog = ioc.getBean(SmartAnimalable.class);smartDog.getSum(10, 2);}
}