spring学习3-第一次测试成功

 参考 

http://www.it165.net/pro/html/201407/18718.html

http://xtu-xiaoxin.iteye.com/blog/630206

http://m.blog.csdn.net/blog/zl3450341/6013727

目标对象类

package com.chuiyuan;

public interface Employee {
	public void signIn ();
}

实现为

package com.chuiyuan;

public class CommonEmployee implements Employee {
	private String name  ;
	
	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	@Override
	public void signIn() {
		System.out.println(name+"已经签到");
	}
	
}

 通知类

然后编写通知类AspectJLogger.java,在该通知类里，通过注入的形式来定义切面、通知以及通知所左右的切点，具体如下： 

package com.chuiyuan;

import java.util.Date;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;

/** 
 * 使用@Aspect 注解的类， Spring 将会把它当作一个特殊的Bean（一个切面），也就是 
 * 不对这个类本身进行动态代理 
 */  
@Aspect
public class AspectJLogger {
	 /** 
     * 必须为final String类型的,注解里要使用的变量只能是静态常量类型的 
     */  
    public static final String EDP = "execution( public * *(..))"; 
    
    @Before(EDP)
    public void logBefore(){
    	 System.out.println("logBefore:现在时间是:"+new Date());  
    }
    
    @After(EDP)    //spring中After通知  
    public void logAfter() {  
        System.out.println("logAfter:现在时间是:"+new Date());  
    }  
    
    @Around(EDP)
    public Object logAround(ProceedingJoinPoint joinPoint){
    	 System.out.println("logAround开始:现在时间是:"+new Date()); //方法执行前的代理处理  
         Object[] args = joinPoint.getArgs();  
         Object obj = null;  
         try {  
             obj = joinPoint.proceed(args);  
         } catch (Throwable e) {  
             e.printStackTrace();  
         }  
         System.out.println("logAround结束:现在时间是:"+new Date());  //方法执行后的代理处理  
         return obj;
    }
    
}

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:aop="http://www.springframework.org/schema/aop"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="http://www.springframework.org/schema/beans 
		http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/aop 
		http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
		http://www.springframework.org/schema/context 
		http://www.springframework.org/schema/context/spring-context-4.0.xsd">
	
    <aop:aspectj-autoproxy/> 
    <bean id="aspect" class="com.chuiyuan.AspectJLogger" />
    <bean id="employee" class="com.chuiyuan.CommonEmployee">
      <property name="name" value="lsj"></property>
    </bean>

</beans>

测试类

package com.chuiyuan;

import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;

public class Test {
	public static void main(String [] args){
		Resource res = new ClassPathResource("applicationContext.xml");
		DefaultListableBeanFactory factory= new DefaultListableBeanFactory ();
		XmlBeanDefinitionReader reader = new XmlBeanDefinitionReader(factory);
		reader.loadBeanDefinitions(res);
		//如果用factory好像不行
		ApplicationContext act = new ClassPathXmlApplicationContext("applicationContext.xml");  
		
		Employee employee= (Employee) act.getBean("employee") ;
		employee.signIn(); 
		
	}  
}

结果

六月 27, 2015 12:14:27 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [applicationContext.xml]
六月 27, 2015 12:14:28 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@1b1a17a: startup date [Sat Jun 27 12:14:28 CST 2015]; root of context hierarchy
六月 27, 2015 12:14:28 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [applicationContext.xml]
logAround开始:现在时间是:Sat Jun 27 12:14:28 CST 2015
logBefore:现在时间是:Sat Jun 27 12:14:28 CST 2015
lsj已经签到
logAround结束:现在时间是:Sat Jun 27 12:14:28 CST 2015
logAfter:现在时间是:Sat Jun 27 12:14:28 CST 2015

一些注意的知识

1.环绕方法通知，环绕方法通知要注意必须给出调用之后的返回值，否则被代理的方法会停止调用并返回null，除非你真的打算这么做。                    

2.只有环绕通知才可以使用JoinPoint的子类ProceedingJoinPoint，个 连接点类型可以调用代理的方法，并获取、改变返回值。