使用注解方式进行aop编程(代码)

刺骨的言语ヽ痛彻心扉 2023-10-07 10:22 22阅读 0赞

UserDao.java接口：

package com.liu.jdk;
    
    public interface UserDao {
        
    	public void addUser();
    	public void deleteUser();
    
    }

UserDaoImpl.java实现类/目标类：

package com.liu.jdk;
    
    import org.springframework.stereotype.Repository;
    
    //目标类
    @Repository("userDao")
    public class UserDaoImpl implements UserDao {
        
    
    	@Override
    	public void addUser() {
        
    		// TODO Auto-generated method stub
    		System.out.println("添加方法");
    		int i  = 1/0;
    	}
    
    	@Override
    	public void deleteUser() {
        
    		// TODO Auto-generated method stub
    		System.out.println("删除方法");
    	}
    
    }

MyAspect.java切面类：

> package com.liu.aspect.annotation;

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.springframework.stereotype.Component;

//切面类  
@Aspect  
@Component  
public class MyAspect \{  
@Pointcut(“execution(\* com.liu.jdk.*.*(…))”)  
//需要一个返回值为void 方法体为空的方法来命名切入点  
private void myPointCut() \{\}

//前置通知
    @Before("myPointCut()")
    public void before(JoinPoint joinPoint) {
    	System.out.println("前置通知开始，模拟检查权限 ");
    	System.out.println("目标类："+joinPoint.getTarget());
    	System.out.println("目标方法为："+joinPoint.getSignature().getName());
    }
    //后置通知
    @AfterReturning("myPointCut()")
    public void afterRunning(JoinPoint joinPoint) {
    	System.out.println("后置通知开始，模拟记录日志");
    	System.out.println("目标方法为："+joinPoint.getSignature().getName());
    }
    
    //环绕通知
    @Around("myPointCut()")
    public Object around(ProceedingJoinPoint proceedingJoinPoint)throws Throwable {
    	System.out.println("环绕通知开始");
    	Object obj = proceedingJoinPoint.proceed();
    	System.out.println("环绕通知结束");
    	return obj;
    }
    
    //异常通知
    @AfterThrowing(value = "myPointCut()",throwing = "e")
    public void afterThrowing(JoinPoint joinPoint,Throwable e) {
    	System.out.println("异常通知,原因在于："+e.getMessage());
    }
    
    //最终通知
    @After("myPointCut()")
    public void after() {
    	System.out.println("最终通知");
    }

ApplicationContext.xml配置文件：

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
    	xmlns:aop="http://www.springframework.org/schema/aop"
    	xmlns:context="http://www.springframework.org/schema/context"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
            http://www.springframework.org/schema/aop
            http://www.springframework.org/schema/aop/spring-aop-4.3.xsd 
            http://www.springframework.org/schema/context
            http://www.springframework.org/schema/context/spring-context-4.3.xsd ">
            
            
            <context:component-scan base-package="com.liu"></context:component-scan>
            
            <aop:aspectj-autoproxy />
    </beans>

Test测试类：

package com.liu.aspect.annotation;
    
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    
    import com.liu.jdk.UserDao;
    
    public class Test {
        
    	public static void main(String[] args) {
        
    		String xmlpath = "com/liu/aspect/annotation/ApplicationContext.xml";
    		
    		ApplicationContext applicationContext = new ClassPathXmlApplicationContext(xmlpath);
    		
    		UserDao userDao = (UserDao) applicationContext.getBean("userDao");
    		
    		userDao.addUser();
    	}
    
    }

运行结果：

环绕通知开始
    前置通知开始，模拟检查权限 
    目标类：com.liu.jdk.UserDaoImpl@5158b42f
    目标方法为：addUser
    添加方法
    最终通知
    异常通知,原因在于：/ by zero