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。
