SpringAOP入门案例

在这里插入图片描述

package com.elf.spring.aop.aspectj;
/*** @author 45* @version 1.0*/
public interface UsbInterface {public void work();
}

package com.elf.spring.aop.aspectj;
import org.springframework.stereotype.Component;
/*** @author 45* @version 1.0*/
@Component //把Phone对象当做一个组件注入容器
public class Phone implements UsbInterface{@Overridepublic void work() {System.out.println("手机开始工作了....");}
}

package com.elf.spring.aop.aspectj;
import org.springframework.stereotype.Component;
/*** @author 45* @version 1.0*/
@Component //将Camera注入到spring容器
public class Camera implements UsbInterface {@Overridepublic void work() {System.out.println("相机开始工作...");}
}

package com.elf.spring.aop.aspectj;import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.*;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;import java.util.Arrays;/*** @author 45* @version 1.0* 切面类 , 类似于我们以前自己写的MyProxyProvider,但是功能强大很多**/
@Order(value = 2)//表示该切面类执行的顺序, value的值越小, 优先级越高
@Aspect //表示是一个切面类[底层切面编程的支撑(动态代理+反射+动态绑定...)]
@Component //会注入SmartAnimalAspect到容器
public class SmartAnimalAspect {//定义一个切入点, 在后面使用时可以直接引用, 提高了复用性@Pointcut(value = "execution(public float com.elf.spring.aop.aspectj.SmartDog.getSum(float, float)))")public void myPointCut() {}//希望将f1方法切入到SmartDog-getSum前执行-前置通知/*** 解读* 1. @Before 表示前置通知:即在我们的目标对象执行方法前执行* 2. value = "execution(public float com.elf.spring.aop.aspectj.SmartDog.getSum(float, float)* 指定切入到哪个类的哪个方法  形式是: 访问修饰符 返回类型 全类名.方法名(形参列表),*     带形参列表是因为方法名可能相同,参数个数不同构成重载,以便区分.* 3. showBeginLog方法可以理解成就是一个切入方法, 这个方法名是可以程序员指定  比如:showBeginLog* 4. JoinPoint joinPoint 在底层执行时，由AspectJ切面框架， 会给该切入方法传入 joinPoint对象* , 通过该方法，程序员可以获取到 相关信息** @param joinPoint*///@Before(value = "execution(public float com.elf.spring.aop.aspectj.SmartDog.getSum(float, float))")//这里我们使用定义好的切入点@Before(value = "myPointCut()")//如果说是一个切入方法,那么形参是JoinPoint joinPoint,用aop来做的开发主要是由aspectj框架来支撑的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();//signature.getName()方法签名指的是:com.elf.spring.aop.aspectj.SmartDog.getSumSystem.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()));//(float, float)}//返回通知：即把showSuccessEndLog方法切入到目标对象方法正常执行完毕后的地方//老韩解读//1. 如果我们希望把目标方法执行的结果，返回给切入方法//2. 可以再 @AfterReturning 增加属性 , 比如 returning = "res"//3. 同时在切入方法增加 Object res//4. 注意: returning = "res" 和 Object res 的 res名字一致//@AfterReturning(value = "execution(public float com.elf.spring.aop.aspectj.SmartDog.getSum(float, float))", returning = "res")//使用切入点@AfterReturning(value = "myPointCut()", 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：即把showExceptionLog方法切入到目标对象方法执行发生异常的的catch{}//@AfterThrowing(value = "execution(public float com.elf.spring.aop.aspectj.SmartDog.getSum(float, float))", throwing = "throwable")//直接使用切入点表达式@AfterThrowing(value = "myPointCut()", 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：即把showFinallyEndLog方法切入到目标方法执行后(不管是否发生异常,都要执行 finally{})//@After(value = "execution(public float com.elf.spring.aop.aspectj.SmartDog.getSum(float, float))")//直接使用切入点@After(value = "myPointCut()")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());}//新的前置通知//@Before(value = "execution(public void com.elf.spring.aop.aspectj.Phone.work()) || execution(public void com.elf.spring.aop.aspectj.Camera.work())")//public void hi(JoinPoint joinPoint) {//    Signature signature = joinPoint.getSignature();//    System.out.println("切面类的hi()-执行的目标方法-" + signature.getName());//}//切入表达式也可以指向接口的方法, 这时切入表达式会对实现了接口的类/对象生效//比如下面我们是对UsbInterface 切入，那么对实现类Phone 和 Camera对象都作用了@Before(value = "execution(public void com.elf.spring.aop.aspectj.UsbInterface.work())")public void hi(JoinPoint joinPoint) {Signature signature = joinPoint.getSignature();System.out.println("切面类的hi()-执行的目标方法-" + signature.getName());}//给Car配置一个前置通知,即将ok1()方法切入到Car类的run()方法前@Before(value = "execution(public void Car.run())")public void ok1(JoinPoint joinPoint) {Signature signature = joinPoint.getSignature();System.out.println("切面类的ok1()-执行的目标方法-" + signature.getName());}//返回通知@AfterReturning(value = "execution(public void Car.run())")public void ok2(JoinPoint joinPoint) {Signature signature = joinPoint.getSignature();System.out.println("切面类的ok2()-执行的目标方法-" + signature.getName());}//异常通知@AfterThrowing(value = "execution(public void Car.run())")public void ok3(JoinPoint joinPoint) {Signature signature = joinPoint.getSignature();System.out.println("切面类的ok3()-执行的目标方法-" + signature.getName());}//后置通知@After(value = "execution(public void Car.run())")public void ok4(JoinPoint joinPoint) {Signature signature = joinPoint.getSignature();System.out.println("切面类的ok4()-执行的目标方法-" + signature.getName());//演示一下JoinPoint常用的方法.joinPoint.getSignature().getName(); // 获取目标方法名joinPoint.getSignature().getDeclaringType().getSimpleName(); // 获取目标方法所属类的简单类名joinPoint.getSignature().getDeclaringTypeName(); // 获取目标方法所属类的类名joinPoint.getSignature().getModifiers(); // 获取目标方法声明类型(public、private、protected)Object[] args = joinPoint.getArgs(); // 获取传入目标方法的参数，返回一个数组joinPoint.getTarget(); // 获取被代理的对象joinPoint.getThis(); // 获取代理对象自己}
}

package com.elf.spring.aop.aspectj;
import org.junit.jupiter.api.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;/*** @author 45* @version 1.0*/
public class AopAspectjTest {@Testpublic void smartDogTestByProxy() {//得到spring容器ApplicationContext ioc =new ClassPathXmlApplicationContext("beans08.xml");//这里我们需要通过接口类型来获取到注入的SmartDog对象-就是代理对象SmartAnimalable smartAnimalable =ioc.getBean(SmartAnimalable.class);//SmartAnimalable smartAnimalable =//        (SmartAnimalable)ioc.getBean("smartDog");smartAnimalable.getSum(10, 2);System.out.println("smartAnimalable运行类型="+ smartAnimalable.getClass());System.out.println("=============================");//smartAnimalable.getSub(100, 20);}@Testpublic void smartDogTestByProxy2() {//得到spring容器ApplicationContext ioc =new ClassPathXmlApplicationContext("beans08.xml");UsbInterface phone = (UsbInterface) ioc.getBean("phone");UsbInterface camera = (UsbInterface) ioc.getBean("camera");phone.work();System.out.println("==================");camera.work();}@Testpublic void test3() {//得到spring容器ApplicationContext ioc =new ClassPathXmlApplicationContext("beans08.xml");Car car = ioc.getBean(Car.class);//说明: car对象仍然是代理对象System.out.println("car的运行类型=" + car.getClass());car.run();}@Testpublic void testDoAround() {//得到spring容器ApplicationContext ioc =new ClassPathXmlApplicationContext("beans08.xml");SmartAnimalable smartAnimalable =ioc.getBean(SmartAnimalable.class);smartAnimalable.getSum(10, 2);}}