一个简单的AOP实例

目标对象的接口:IStudent.java

1   /** */ /**
2  *
3   */
4  package  com.dragon.study;
5 
6   /** */ /**
7  *  @author  dragon
8  *
9   */
10   public   interface  IStudent   {
11    
12      public   void  addStudent(String name);
13 }
14 

目标类:StudentImpl.java

1   /** */ /**
2  *
3   */
4  package  com.dragon.study.Impl;
5 
6  import  com.dragon.study.IStudent;
7 
8   /** */ /**
9  *  @author  dragon
10  *
11   */
12   public   class  StudentImpl  implements  IStudent  {
13 
14        public   void  addStudent(String name)  {
15          System.out.println( " 欢迎  " + name + "  你加入Spring家庭! " );
16      }
17 }
18 


前置通知:BeforeAdvice.java

1   /** */ /**
2  *
3   */
4  package  com.dragon.Advice;
5 
6  import  java.lang.reflect.Method;
7 
8  import  org.springframework.aop.MethodBeforeAdvice;
9 
10   /** */ /**
11  *  @author  dragon
12  *
13   */
14   public   class  BeforeAdvice  implements  MethodBeforeAdvice  {
15 
16        public   void  before(Method method,Object[] args, Object target)
17                  throws  Throwable  {
18          
19           System.out.println( " 这是BeforeAdvice类的before方法. " );
20          
21       }
22 }
23 

后置通知:AfterAdvice.java

1/** *//**
2 *
3 */
4package com.dragon.Advice;
5
6import java.lang.reflect.Method;
7
8import org.springframework.aop.AfterReturningAdvice;
9
10/** *//**
11 * @author dragon
12 *
13 */
14public class AfterAdvice implements AfterReturningAdvice{
15   
16    public void afterReturning(Object returnValue ,Method method,
17                   Object[] args,Object target) throws Throwable{
18        System.out.println("这是AfterAdvice类的afterReturning方法.");
19    }
20     
21
22}
23

环绕通知:CompareInterceptor.java

1/** *//**
2 *
3 */
4package com.dragon.Advice;
5
6import org.aopalliance.intercept.MethodInterceptor;
7import org.aopalliance.intercept.MethodInvocation;
8
9
10/** *//**
11 * @author dragon
12 *
13 */
14public class CompareInterceptor implements MethodInterceptor{
15
16      public Object invoke(MethodInvocation invocation) throws Throwable{
17          Object result = null;
18         String stu_name = invocation.getArguments()[0].toString();
19         if ( stu_name.equals("dragon")){
20             //如果学生是dragon时,执行目标方法,
21              result= invocation.proceed();
22             
23         } else{
24             System.out.println("此学生是"+stu_name+"而不是dragon,不批准其加入.");
25         }
26       
27          return result;
28      }
29}
30

配置文件applicationContext.xml

1<?xml version="1.0" encoding="UTF-8"?>
2<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">
3
4<beans>
5
6<bean id="beforeAdvice" class="com.dragon.Advice.BeforeAdvice"></bean>
7<bean id="afterAdvice" class="com.dragon.Advice.AfterAdvice"></bean>
8<bean id="compareInterceptor" class="com.dragon.Advice.CompareInterceptor"></bean>
9<bean id="studenttarget" class="com.dragon.study.Impl.StudentImpl"></bean>
10
11<bean id="student" class="org.springframework.aop.framework.ProxyFactoryBean">
12  <property name="proxyInterfaces">
13    <value>com.dragon.study.IStudent</value>
14  </property>
15  <property name="interceptorNames">
16    <list>
17     <value>beforeAdvice</value>
18     <value>afterAdvice</value>
19    <value>compareInterceptor</value> 
20    </list>
21  </property>
22  <property name="target">
23    <ref bean="studenttarget"/>
24  </property>
25
26</bean>
27
28
29
30
31</beans>


  现在开始写测试类,Test.java 
import org.springframework.context.ApplicationContext;  
import org.springframework.context.support.FileSystemXmlApplicationContext;  
 
/** 
*/ 
public class Test {  
 
    public static void main(String[] args) {  
        ApplicationContext ctx = new FileSystemXmlApplicationContext("/src/applicationContext.xml");  
        Student s = (Student) ctx.getBean("student");  
        s.addStudent("ss");   
    }  
} 
http://jff.iteye.com/blog/221458