异常抛出增强

　　异常抛出增强的特点是在目标方法抛出异常时织入增强处理。

注意：ThrowsAdvice接口中并没有定义任何方法，但是我们在定义异常抛出的增强方法时必须遵守以下方法签名。

void afterThrowing(Method method,Object[] args, Object target, RuntimeException e)

1.首先人为制造一个异常,

package com.dao.impl;

import com.dao.IUserDao;
import com.domain.User;

public class IUserDaoImpl implements IUserDao {

    @Override
    public void save(User user) {
        // TODO Auto-generated method stub
        System.out.println("哇塞，保存用户信息了");
        //故意制造异常
        throw new RuntimeException("看到这个别紧张，是故意制造的异常");
    }

}

2.写个异常处理类

package com.aop;

import java.sql.SQLException;
import java.lang.reflect.Method;
import org.apache.log4j.Logger;
import org.springframework.aop.ThrowsAdvice;

public class ErrorLogger implements ThrowsAdvice {

    private static final Logger log = Logger.getLogger(ErrorLogger.class);
    
    public void afterThrowing(Method method,Object[] args, Object target, RuntimeException e){
        log.error(method.getName()+"方法发生异常:"+e);
    }
    public void afterThrowing(Method method,Object[] args, Object target, SQLException ex){
        log.error(method.getName()+"方法发生异常:"+ex);
    }
}

3.配置spring配置文件，记得到aop空间

<bean id="dao" class="com.dao.impl.IUserDaoImpl"></bean>
    <bean id="biz" class="com.biz.impl.IUserBizImpl">
        <property name="dao" ref="dao"></property>
    </bean>
    <bean id="errorlog" class="com.aop.ErrorLogger"></bean>
    <aop:config>
    <!-- <aop:pointcut expression="execution(public void save(com.domain.User))" id="pointcut"/>-->
        <aop:pointcut expression="execution(* com.biz.IUserBiz.*(..))" id="pointcut"/>
        <aop:advisor advice-ref="errorlog" pointcut-ref="pointcut"/>
    </aop:config>

4.编写测试类

package com.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.biz.IUserBiz;
import com.domain.User;

/**
 * 
 * @author Mr
 * aop测试类
 */
public class Test {

    public static void main(String[] args) {
        //解析配置文件
        ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml");
        
        IUserBiz biz = (IUserBiz) ac.getBean("biz");
        User user = new User();
        user.setUname("小老虎");
        biz.save(user);
    }

}

5.测试效果