Web开发通用监控类解决方案（代码零侵入性）

我们开发网站的过程中，经常会碰到这种情况，当调用某个类中函数的时候，需要记录一些东西或触发某些事件，如何来实现呢？如当缓存中的对象不是最新时，需及时更新缓存对象，当调用某些类的某些方法时，需要记录某些日志信息等，这种应用无处不在，我们如何实现他，利用Spring框架的AOP为例，记录一下他的实现方法

在applicationContext.xml 配置文件中加入类似如下配置信息

<bean id="commonAdvise" class="cn.hj.advise.CommonAdvise"></bean>
 <bean id="commonProxy" class="org.springframework.aop.framework.ProxyFactoryBean">
     <property name="target">
         <ref bean="groupService" />
     </property>
     <property name="proxyInterfaces">
         <value>cn.hj.service.IGroupService</value>
     </property>
     <property name="interceptorNames">
         <list>
             <value>commonAdvise</value>
         </list>
     </property>
    </bean>

<bean id="commonAdvise" class="cn.hj.advise.CommonAdvise"></bean>  
<bean id="commonProxy" class="org.springframework.aop.framework.ProxyFactoryBean">  
    <property name="target">  
        <ref bean="groupService" />  
    </property>  
    <property name="proxyInterfaces">  
        <value>cn.hj.service.IGroupService</value>  
    </property>  
    <property name="interceptorNames">  
        <list>  
            <value>commonAdvise</value>  
        </list>  
    </property>  
   </bean>  

两个类的源码如下

public class CommonAdvise implements AfterReturningAdvice{
     private GroupService groupService;
     public GroupService getGroupService() {
         return groupService;
    }
     public void setGroupService(GroupService groupService) {
         this.groupService = groupService;
    }
     public void afterReturning(Object returnValue, Method method, Object[] target_arg,
             Object target) throws Throwable {
         System.out.println("===========================");
         System.out.println("目标方法返回值："+returnValue+"，目标方法："+method+"，目标对象："+target+"目标方法参数列表:\n");
         if(target_arg!=null){
             for(int i=0;i<target_arg.length;i++){
                 System.out.println("Object["+i+"]:"+target_arg[i]);
            }
        }
         System.out.println("===========================");

    }

}

public class CommonAdvise implements AfterReturningAdvice{   
    private GroupService groupService;   
    public GroupService getGroupService() {   
        return groupService;   
    }   
    public void setGroupService(GroupService groupService) {   
        this.groupService = groupService;   
    }   
    public void afterReturning(Object returnValue, Method method, Object[] target_arg,   
            Object target) throws Throwable {   
        System.out.println("===========================");   
        System.out.println("目标方法返回值："+returnValue+"，目标方法："+method+"，目标对象："+target+"目标方法参数列表:\n");   
        if(target_arg!=null){   
            for(int i=0;i<target_arg.length;i++){   
                System.out.println("Object["+i+"]:"+target_arg[i]);   
            }   
        }   
        System.out.println("===========================");   
       
    }   
  
}  

 

public interface IGroupService {
     public void addGroup(Group group);
     public void delGroup(Group group);
     public void modGroup(Group group);
     public Group findGroup(String groupid);
     public List listGroup();
}

public interface IGroupService {   
    public void addGroup(Group group);   
    public void delGroup(Group group);   
    public void modGroup(Group group);   
    public Group findGroup(String groupid);   
    public List listGroup();   
} 

测试代码
在我程序的任何地方调用IGroupService的listGroup时，都会自动执行commonAdvise中的代码，打印信息如下：

===========================
 目标方法返回值：[cn.hj.model.Group@1bb205a, cn.hj.model.Group@48fbc0, cn.hj.model.Group@18837f1]
 目标方法：public abstract java.util.List cn.hj.service.IGroupService.listGroup()
 目标对象：cn.hj.service.GroupService@10f0a0
目标方法参数列表:
===========================

===========================   
目标方法返回值：[cn.hj.model.Group@1bb205a, cn.hj.model.Group@48fbc0, cn.hj.model.Group@18837f1]   
目标方法：public abstract java.util.List cn.hj.service.IGroupService.listGroup()   
目标对象：cn.hj.service.GroupService@10f0a0  
目标方法参数列表:   
===========================  

这种方式绝对是代码零侵入性，推荐大家使用。