Spring中的AOP(面向切面编程)

Spring框架中采用动态代理来实现方法的增强&＃xff0c;称之为AOP即面向切面编程
要增强的方法称为切入点方法
AOP中的通知(即增强的内容)分为&＃xff1a;
前置通知&＃xff1a;在切入点方法之前执行
后置通知&＃xff1a;在切入点方法正常执行之后执行
异常通知&＃xff1a;在切入点方法出现异常之后执行
最终通知&＃xff1a;最终都会执行的方法
环绕通知&＃xff1a;可以通过代码来实现上述的四个通知

bean.xml文件的配置&＃xff08;基于xml的配置&＃xff09;

增强类

package com.wuxudong.log;import org.aspectj.lang.ProceedingJoinPoint;public class Logger {public void beforeLog(){System.out.println("前置通知");}public void afterReturningLog(){System.out.println("后置通知");}public void afterThrowingLog(){System.out.println("异常通知");}public void afterLog(){System.out.println("最终通知");}public Object aroundLog(ProceedingJoinPoint pjp){//定义返回值Object rtValue&＃61;null;try{//前置通知System.out.println("前置通知");Object [] args&＃61;pjp.getArgs();//执行切入点方法rtValue&＃61;pjp.proceed(args);//后置通知System.out.println("后置通知");} catch (Throwable throwable) {throwable.printStackTrace();//异常通知System.out.println("异常通知");} finally {System.out.println("最终通知");}return rtValue;}
}


基于注解的aop配置

bean.xml文件

增强类

package com.wuxudong.log;import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.springframework.stereotype.Component;&＃64;Component("logger")
&＃64;Aspect
public class Logger {&＃64;Pointcut("execution(* com.wuxudong.service.impl.*.*(..))")public void pt1(){}&＃64;Before("pt1()")public void beforeLog(){System.out.println("前置通知");}&＃64;AfterReturning("pt1()")public void afterReturningLog(){System.out.println("后置通知");}&＃64;AfterThrowing("pt1()")public void afterThrowingLog(){System.out.println("异常通知");}&＃64;After("pt1()")public void afterLog(){System.out.println("最终通知");}&＃64;Around("pt1()")public Object aroundLog(ProceedingJoinPoint pjp){//定义返回值Object rtValue&＃61;null;try{//前置通知System.out.println("前置通知");Object [] args&＃61;pjp.getArgs();//执行切入点方法rtValue&＃61;pjp.proceed(args);//后置通知System.out.println("后置通知");} catch (Throwable throwable) {throwable.printStackTrace();//异常通知System.out.println("异常通知");} finally {System.out.println("最终通知");}return rtValue;}
}