引出对Spring底层实现再思考

package com.zzw.spring.aop; import org.aspectj.lang.JoinPoint; import org.aspectj.lang.Signature; import org.aspectj.lang.annotation.*; import org.springframework.stereotype.Component; import java.util.Arrays; /** * @author 赵志伟 * @version 1.0 */ @SuppressWarnings({"all"}) //这是一个切面类 @Aspect @Component 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.zzw.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()-方法执行前-日志-方法名-" + signature.getName() + "-参数 " + Arrays.asList(joinPoint.getArgs())); } //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 @AfterReturning(value = "execution(public float com.zzw.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: 即把showExceptionLog方法切入到目标对象方法执行发生异常后的catch{} @AfterThrowing(value = "execution(public float com.zzw.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: 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.zzw.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()); } }