MethodInvokingTimerTaskFactoryBean 的使用

Question

<bean id="demoTask"  
           class="com.cn.action.AutonSengSms"/>      <bean id="timerTaskBean"  
          class="org.springframework.scheduling.timer.MethodInvokingTimerTaskFactoryBean">  
        <property name="targetObject">  
            <ref bean="demoTask"/>  
        </property>  
        <property name="targetMethod">  
            <value>sendsms</value>  
        </property>         
    </bean>  
          
    <bean id="scheduledTimerTask"  
          class="org.springframework.scheduling.timer.ScheduledTimerTask">  
             <!--这里定义定时任务的对象的位置--> 
        <property name="timerTask">  
            <ref bean="timerTaskBean"/>  
        </property>  
        <!--这里定义每5秒钟程序执行一次--> 
        
        <property name="period">  
            <value>5000</value>  
        </property>  
            <!--这里定义程序启动1秒钟后开始执行--> 
         <property name="delay">  
            <value>1000</value>  
        </property>          
    </bean>  
      
    <bean id="timerFactoryBean"  
          class="org.springframework.scheduling.timer.TimerFactoryBean">  
        <property name="scheduledTimerTasks">  
            <list>  
                <ref bean="scheduledTimerTask"/>  
            </list>  
        </property>  
    </bean>  在applicationContext里这样配置了。为什么没有启动起来了。各位帮忙