spring切面：注解：抛出异常增强

用注解定义增强
在项目中添加spring AOP相关的jar文件；
使用注解定义前置增强和后置增强实现日志功能；
编写spring配置文件，织入注解定义的增强。

1.aop/UserLogger注释增强类

package aop;import java.util.Arrays;import org.apache.log4j.Logger;import org.aspectj.lang.JoinPoint;import org.aspectj.lang.annotation.AfterThrowing;import org.aspectj.lang.annotation.Aspect;import org.aspectj.lang.annotation.Before;import org.aspectj.lang.annotation.AfterReturning;@Aspectpublic class UserLogger {    private static final Logger log = Logger.getLogger(UserLogger.class);@Before("execution(* biz.impl.*.*(..))")public void before(JoinPoint jp){    System.out.println("注解前置增强");    System.out.println("调用的方法："+jp.getSignature()+"，传递参数："+Arrays.toString(jp.getArgs()));}@AfterReturning(pointcut="execution(* biz.impl.*.*(..))",returning="returnResult")public void afterReturning(JoinPoint jp,Object returnResult){    System.out.println("注解后置增强");    System.out.println("调用的方法："+jp.getSignature()+"，传递参数："+Arrays.toString(jp.getArgs())+"，返回参数："+returnResult);}@AfterThrowing(pointcut="execution(* biz.impl.*.*(..))",throwing="e")public void afterThrowing(JoinPoint jp,RuntimeException e){    log.error("调用的方法："+jp.getSignature()+"，传递参数："+Arrays.toString(jp.getArgs())+"，方法发生异常："+e);}}

2.applicationContext.xml配置文件

<?xml version="1.0" encoding="UTF-8"?><beans    xmlns="http://www.springframework.org/schema/beans"    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xmlns:p="http://www.springframework.org/schema/p"    xmlns:aop="http://www.springframework.org/schema/aop"    xsi:schemaLocation="http://www.springframework.org/schema/beans     http://www.springframework.org/schema/beans/spring-beans-3.1.xsd    http://www.springframework.org/schema/aop    http://www.springframework.org/schema/aop/spring-aop-3.1.xsd"> <!--  将前置增强类配成bean,交给spring管理     <bean id="loggerBefore" class="aop.LoggerBefore"></bean>    将后置增强类配成bean,交给spring管理    <bean id="afterReturning" class="aop.AfterReturning"></bean>    配置切面(将增强类关联给某个条件范围内的方法)    <bean id="errorLogger" class="aop.ErrorLogger"></bean>  -->    <bean id="aroundLogger" class="aop.AroundLogger"></bean>    <bean class="aop.UserLogger"></bean>    <aop:aspectj-autoproxy></aop:aspectj-autoproxy>    <!-- <aop:config>       配置切入点pointcut       <aop:pointcut expression="execution(* biz.impl.*.*(..))" id="myPoint"/>       <aop:advisor advice-ref="loggerBefore" pointcut-ref="myPoint"/>       <aop:advisor advice-ref="afterReturning" pointcut-ref="myPoint"/>       <aop:advisor advice-ref="errorLogger" pointcut-ref="myPoint"/>       <aop:advisor advice-ref="aroundLogger" pointcut-ref="myPoint"/>    </aop:config> -->    <bean id="userBiz" class="biz.impl.UserBizImpl" p:userDao-ref="userDao">      <!--  <property name="userDao" ref="userDao2"></property> -->    </bean>   <bean id="userDao" class="dao.impl.UserDaoImpl" />   <bean id="userDao2" class="dao.impl.UserDaoImpl2" /></beans>

3.dao.impl/UserDaoImpl类

package dao.impl;import javax.management.RuntimeErrorException;import dao.UserDao;import entity.User;public class UserDaoImpl implements UserDao {    @Override    public User findUser() {        System.out.println("===========Dao层查询User 1==============");        User u=new User("Tom",22);        throw new RuntimeException("出现异常");        //return u;    }}

4.Test方法

public static void main(String[] args) {        //加载spring容器,解析配置文件        ApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");         UserBiz userBiz=(UserBiz) ac.getBean("userBiz");         User u= userBiz.getUser(101);         System.out.println(u.getUname()+","+u.getAge());    }