AOP-通知-异常通知

顾名思义，目标方法发生异常植入的切面
异常通知类需要实现​​​ThrowsAdvice​​​接口，你会发现​​ThrowsAdvice​​​没有需要实现的方法

在源码中有猫腻

* <pre class="code">public void afterThrowing(Exception ex)</pre>
* <pre class="code">public void afterThrowing(RemoteException)</pre>
* <pre class="code">public void afterThrowing(Method method, Object[] args, Object target, Exception ex)</pre>
* <pre class="code">public void afterThrowing(Method method, Object[] args, Object target, ServletException ex)</pre>
*

这当中有四个方法可以实现，下面我实现第一个
接口

package com.hk.spring.aop04;

public interface SomeService {

    public void doFirst();
    public void doSecond();
}

接口实现

package com.hk.spring.aop04;

public class SomeServiceImpl implements SomeService {

    @Override
    public void doFirst() {

        System.out.println("主业务doFirst");
        //搞个异常出来
        int a = 4;
        int b = 0;
        a = a / b;
    }

    @Override
    public void doSecond() {

        System.out.println("主业务doSecond");
    }

}

异常通知

package com.hk.spring.aop04;


import org.springframework.aop.ThrowsAdvice;

/**
 *  异常通知
 * @author 浪丶荡
 *
 */
public class MyThrowsAdvice implements ThrowsAdvice {

    //在目标方法发异常时执行
    public void afterThrowing(Exception ex){
        System.out.println("执行异常通知方法：发生的异常是——"+ex.getMessage());
    }

}

配置文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN 2.0//EN"
        "http://www.springframework.org/dtd/spring-beans-2.0.dtd">

<beans>
    <bean name = "someService" class="com.hk.spring.aop04.SomeServiceImpl"></bean>
    <!-- 注册通知 -->
    <bean name = "myThrowsAdvice" class="com.hk.spring.aop04.MyThrowsAdvice"></bean>
    <!-- 生成代理对象 -->
    <bean name = "serviceProxy" class="org.springframework.aop.framework.ProxyFactoryBean">
    <!-- 配置代理对象的目标对象属性 （类加载器）-->
    <property name="target" ref="someService"/>
    <!-- 或者这样配置
    <property name="targetName" value="someService"/>
    -->
    <!-- 配置切面 （方法）-->
    <property name="interceptorNames" value="myThrowsAdvice"/>
    <!-- 接口通过private boolean autodetectInterfaces = true可以被找到 -->
    </bean>

</beans>

测试

package com.hk.spring.aop04;


import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class Mytest {

    @Test
    public void test1(){
        String resoure = "com/hk/spring/aop04/applicationContext.xml";
        ApplicationContext ac = new ClassPathXmlApplicationContext(resoure);
        SomeService someService = (SomeService) ac.getBean("serviceProxy");
        someService.doFirst();
        someService.doSecond();
    }
}

结果

主业务doFirst
执行异常通知方法：发生的异常是——/ by zero