後端-框架-Spring-AOP-Declaring Advice

記錄日誌類

package
 
 cn.aop;

import java.util.Arrays;

import org.apache.log4j.Logger;
import org.aspectj.lang.JoinPoint;

public class UserServiceLogger {
	public static Logger logger = Logger.getLogger(UserServiceLogger.class);
	public void before(JoinPoint jp){
		logger.info("呼叫物件："+jp.getTarget()+"方法："+jp.getSignature
 
()+"方法引數"+Arrays.toString(jp.getArgs()));
	}
	public void afterReturn(JoinPoint jp,Object result){
		logger.info("呼叫物件："+jp.getTarget()+"方法："+jp.getSignature()+"方法返回值"+result);
	}
	public void afterThrow(JoinPoint jp,Exception e){
		logger.error(jp.getSignature().getName()+"捕捉到異常"+e);
	}
	public void
 
 after(JoinPoint jp){
		logger.info(jp.getSignature().getName()+"最終增強");
	}
	public Object around(ProceedingJoinPoint jp) throws Throwable{
		logger.info("呼叫物件："+jp.getTarget()+"方法："+jp.getSignature()+"方法引數"+Arrays.toString(jp.getArgs()));
		try {
			Object result = jp.proceed();
			logger.info("呼叫物件："+jp.getTarget()+"方法："+jp.getSignature()+"方法返回值"+result);
			return result;
		} catch (Throwable e) {
			logger.error(jp.getSignature().getName()+"捕捉到異常"+e);
			throw e;
		} finally{
			logger.info(jp.getSignature().getName()+"方法結束");
		}
	}
}

使用者業務類

package cn.service;

import cn.service.UserService;
import cn.dao.UserDao;
import cn.entity.User;

/**
 * 使用者業務類，實現對User功能的業務管理
 */
public class UserServiceImpl implements UserService {

	// 宣告介面型別的引用，和具體實現類解耦合
	private UserDao dao;

	// dao 屬性的setter訪問器，會被Spring呼叫，實現設值注入
	public void setDao(UserDao dao) {
		this.dao = dao;
	}

	public void addNewUser(User user) {
		// 呼叫使用者DAO的方法儲存使用者資訊
		dao.save(user);
		throw new RuntimeException("測試異常");
	}
}

ApplicationContext配置

<?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:aop="http://www.springframework.org/schema/aop" 
    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.xsd"
    >
    
	<bean id="UserDao" class="cn.dao.UserDaoImpl"></bean>
	<bean id="UserService" class="cn.service.UserServiceImpl">
		<property name="dao" ref="UserDao"/>
	</bean>
	<bean id="UserServiceLogger" class="cn.aop.UserServiceLogger"></bean>
	
	<aop:config>
		<!-- 切入點,切入執行增強的方法 -->
		<aop:pointcut expression="execution(public void addNewUser(cn.entity.User))" id="pointcut"/>
		<!-- 切入面,增強方法定義 -->
		<aop:aspect ref="UserServiceLogger">
			<aop:before method="before" pointcut-ref="pointcut"/>
			<!-- method必須與具體類中方法名一致 -->
			<aop:after-returning method="afterReturn" pointcut-ref="pointcut" returning="result"/>
			<aop:after-throwing pointcut-ref="pointcut" throwing="e" method="afterThrow"/>
			<aop:after pointcut-ref="pointcut" method="after"/>
		</aop:aspect>
			<aop:around pointcut-ref="pointcut" method="around"/>
	</aop:config>
	
</beans>

JUnit測試

package test;

import static org.junit.Assert.*;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import cn.entity.User;
import cn.service.UserService;
import cn.service.UserServiceImpl;

public class UserServiceTest {

	@Test
	public void test() {
		ApplicationContext context = new ClassPathXmlApplicationContext("ApplicationContext.xml");
		UserService us = (UserService) context.getBean("UserService");
		User user = new User();
		user.setId(123);
		user.setPassword("1234444");
		user.setUsername("Caedios");
		user.setEmail("Gmail");
		us.addNewUser(user);
	}
}

別忘了,expression表示式

<aop:pointcut expression="execution(public void addNewUser(cn.entity.User))" id="pointcut"/>