宣告切面類

　　@Aspect(切面)：通常是一個類，裡面可以定義切入點和通知

配置切入點和通知

LogAdvice.java

package net.cybclass.sp.aop;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;

 
//能被掃描
@Component
//告訴Spring，這是一個切面類，裡面可以定義切入點和通知
@Aspect
public class LogAdvice {
    //切入點表示式
    @Pointcut("execution(* net.cybclass.sp.servicce.VideoServiceImpl.*(..))")
    public void aspect(){

    }
    //前置通知
    @Before("aspect()")
    public void beforeLog(JoinPoint joinPoint) {
        System.out.println(
 
"LogAdvice beforeLog 被呼叫了");
    }
    //後置通知
    @Before("aspect()")
    public void afterLog(JoinPoint joinPoint) {
        System.out.println("LogAdvice afterLog 被呼叫了");
    }
}

開啟Spring AOP註解配置

package net.cybclass.sp.aop;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
 
import org.springframework.stereotype.Component;
//告訴Spring，這個類可以被掃描
@Component
//掃描包
@ComponentScan("net.cybclass")
@EnableAspectJAutoProxy //開啟了spring對aspect的支援
public class AnnotationConfig {
}

VideoService.java

package net.cybclass.sp.servicce;

import net.cybclass.sp.domain.Video;

public interface VideoService {
    int save(Video video);
    Video findById(int id);
}

VideoServiceImpl.java

package net.cybclass.sp.servicce;

import net.cybclass.sp.domain.Video;
import org.springframework.stereotype.Component;

//@Component("videoService") //相當於配置bean的id
@Component() //相當於配置bean的id
public class VideoServiceImpl implements VideoService{
    public int save(Video video) {
        System.out.println("儲存Video");
        return 0;
    }

    public Video findById(int id) {
        System.out.println("根據id找視訊");
        return new Video();
    }
}

演示