循序渐进学习SPRING(二)

定时执行策略的应用 
（一）使用Quartz
Quartz是opensymphony组织的一个框架，请参见www.opensymphony.com/quartz
如果要使用quartz来实现定时执行策略，首先需要创建一个任务。即写一个扩展QuartzJobBean的Bean

例如：

public class XmlPublishJob extends QuartzJobBean {
    protected void executeInternal(JobExecutionContext arg0) throws JobExecutionException {
        //do something;
    }
}

然后在spring的config文件中对定时执行策略进行定义
<!-- 增加定时执行发布程序的策略 By Roy 2005-11-11 -->

<!--定义任务-->
 <bean name="publishJob" class="org.springframework.scheduling.quartz.JobDetailBean">
   <property name="jobClass">
     <value>com.mywap.common.publish.XmlPublishJob</value>
   </property>
   <property name="jobDataAsMap">
     <map>
       <entry key="timeout"><value>50</value></entry>
       <entry key="pageinfoService"><ref bean="pageinfoService"></ref></entry>
       <entry key="rowsinfoService"><ref bean="rowsinfoService"></ref></entry>
       <entry key="columninfoService"><ref bean="columninfoService"></ref></entry>
     </map>
   </property>
 </bean>

<!--设置触发器-->
 <bean id="publishTrigger" class="org.springframework.scheduling.quartz.SimpleTriggerBean">
   <property name="jobDetail">
     <!-- see the example of method invoking job above -->   
     <ref bean="publishJob"/>
   </property>
   <property name="startDelay">
     <!-- 10 seconds -->
     <value>1000</value>
   </property>
   <property name="repeatInterval">
     <!-- repeat every 50 seconds -->
     <value>5000</value>
   </property>
 </bean>

<!--进行触发-->
 <bean class="org.springframework.scheduling.quartz.SchedulerFactoryBean">
   <property name="triggers">
     <list>
       <ref local="publishTrigger"/>
     </list>
   </property>
 </bean>
(二)使用JDK Timer
首先需要创建定制的timers
public class CheckEmailAddresses extends TimerTask {

  private List emailAddresses;
 
  public void setEmailAddresses(List emailAddresses) {
    this.emailAddresses = emailAddresses;
  }
 
  public void run() {
 
    // iterate over all email addresses and archive them
   
  }
}

然后在spring的配置文件中配置

<bean id="checkEmail" class="examples.CheckEmailAddress">
  <property name="emailAddresses">
    <list>
      <value>[e-mail]</value>
      <value>[e-mail]</value>
      <value>[e-mail]</value>
    </list>
  </property>
</bean>

<bean id="scheduledTask" class="org.springframework.scheduling.timer.ScheduledTimerTask">
  <!-- wait 10 seconds before starting repeated execution -->
  <property name="delay">
    <value>10000</value>
  </property>
  <!-- run every 50 seconds -->
  <property name="period">
    <value>50000</value>
  </property>
  <property name="timerTask">
    <ref local="checkEmail"/>
  </property>
</bean>

<bean id="timerFactory" class="org.springframework.scheduling.timer.TimerFactoryBean">
  <property name="scheduledTimerTasks">
    <list>
      <!-- see the example above -->
      <ref local="scheduledTask"/>
    </list>
  </property>
</bean>