Spring aop 切面编程

package cn.annals.demo.proc.aop;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

//声明这是一个组件
@Component
//声明这是一个切面Bean
@Aspect
public class proc_service_aop {

    private final Logger LOG = LoggerFactory.getLogger(this.getClass());
    
    //配置切入点,该方法无方法体,主要为方便同类中其他方法使用此处配置的切入点
    //@Pointcut("execution(public * cn.annals.demo.proc.service..*(..))")
    @Pointcut("execution(public * cn.annals.demo.proc.service..*.save(..))")
    public void aspect(){}
    
    /*
     * 配置前置通知,使用在方法aspect()上注册的切入点
     * 同时接受JoinPoint切入点对象,可以没有该参数
     */
    @Before("aspect()")
    public void before(JoinPoint joinPoint){
        if(LOG.isInfoEnabled()){
            LOG.info("before " + joinPoint);
        }
    }
    
    //配置后置通知,使用在方法aspect()上注册的切入点
    @After("aspect()")
    public void after(JoinPoint joinPoint){
        if(LOG.isInfoEnabled()){
            LOG.info("after " + joinPoint);
        }
    }
    
    //配置环绕通知,使用在方法aspect()上注册的切入点
    @Around("aspect()")
    public void around(ProceedingJoinPoint joinPoint){
        long start = System.currentTimeMillis();
        try {
            joinPoint.proceed();
            long end = System.currentTimeMillis();
            if(LOG.isInfoEnabled()){
                LOG.info("around " + joinPoint + "\tUse time : " + (end - start) + " ms!");
            }
        } catch (Throwable e) {
            long end = System.currentTimeMillis();
            if(LOG.isInfoEnabled()){
                LOG.info("around " + joinPoint + "\tUse time : " + (end - start) + " ms with exception : " + e.getMessage());
            }
        }
    }
    
    //配置后置返回通知,使用在方法aspect()上注册的切入点
    @AfterReturning("aspect()")
    public void afterReturn(JoinPoint joinPoint){
        if(LOG.isInfoEnabled()){
            LOG.info("afterReturn " + joinPoint);
        }
    }
    
    //配置抛出异常后通知,使用在方法aspect()上注册的切入点
    @AfterThrowing(pointcut="aspect()", throwing="ex")
    public void afterThrowing(JoinPoint joinPoint, Exception ex){
        if(LOG.isInfoEnabled()){
            LOG.info("afterThrow " + joinPoint + "\t" + ex.getMessage());
        }
    }
}