Spring中的Advisor，Advice，Pointcut

一、Spring中的Advisor，Advice，Point概述

1、Advisor：充当Advice和Pointcut的适配器，类似使用Aspect的@Aspect注解的类（前一章节所述）。一般有advice和pointcut属性。

祖先接口为org.springframework.aop.Advisor,应用中可直接使用org.springframework.aop.support.DefaultPointcutAdvisor

2、Advice：用于定义拦截行为，祖先接口为org.aopalliance.aop.Advice，该接口只是标识接口，应用中可直接实现BeforeAdvice ，ThrowsAdvice，MethodInterceptor ，AfterReturningAdvice ，IntroductionInterceptor 等子接口

3、Pointcut：用于定义拦截目标集合，祖先接口为org.springframework.aop.Pointcut

二、Spring中的Advisor，Advice，Point的应用

1、编写Advisor实现类

在此可直接使用org.springframework.aop.support.DefaultPointcutAdvisor

2、编写Advice实现类

public class PlayAdvice implements MethodBeforeAdvice{
 public void before(Method method, Object[] args, Object target)
   throws Throwable {
  System.out.println("my before advice");
 // method.invoke(target, args); 如果再调用这句，则目标方法会执行多一次
 }
}

3、编写Pointcut实现类
public class PlayPointcut implements Pointcut {
 public ClassFilter getClassFilter() {
  return new PlayClassFilter();
 }
 public MethodMatcher getMethodMatcher() {
  return new PlayMethodMatcher();
 }
}
//PlayClassFilter的定义

class PlayClassFilter implements ClassFilter {
 public boolean matches(Class clazz) {
  if(clazz.getSimpleName().equals("Play"))
   return true;
  return false;
 }
}

//PlayMethodMatcher的定义

class PlayMethodMatcher implements MethodMatcher {
 public boolean isRuntime() {
  return true;
 }
 public boolean matches(Method method, Class c) {
  if(c.getSimpleName().equals("Play")&&method.getName().contains("Service"))
   return true;
  return false;
 }
 public boolean matches(Method method, Class c, Object[] args) {
  if(c.getSimpleName().equals("Play")&&method.getName().contains("Service"))
   return true;
  return false;
 }
}

4、编写目标类

public class Play {

  public void playService(String what){
  System.out.println("play "+what);
 }
}

5、在配置文件中配置

<bean id="adviceBean" class="com.hss.sp.aop.PlayAdvice"/>
<bean id="pointcutBean" class="com.hss.sp.aop.PlayPointcut"/>
<bean id="playService" class="com.hss.sp.service.Play"/>
<bean
   class="org.springframework.aop.support.DefaultPointcutAdvisor">
   <property name="advice" ref="adviceBean"></property>
   <property name="pointcut" ref="pointcutBean"></property>
</bean>

6、测试，结果

 BeanFactory bf=new ClassPathXmlApplicationContext("applicationContext.xml");
  Play play=(Play)bf.getBean("playService");
  play.playService("pingpong");

输出：

my before advice
play pingpong

转自----http://blog.sina.com.cn/s/blog_5198c7370100hw1p.html