Quartz在Spring中动态设置cronExpression

什么是动态定时任务：是由客户制定生成的，服务端只知道该去执行什么任务，但任务的定时是不确定的（是由客户制定）。

这样总不能修改配置文件每定制个定时任务就增加一个trigger吧，即便允许客户修改配置文件，但总需要重新启动web服务啊，研究了下Quartz在Spring中的动态定时，发现<bean id="cronTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean" >

         <property name="jobDetail" ref="schedulerJobDetail"/>

         <property name="cronExpression">

             <value>0/10 * * * * ?</value>

         </property>

     中cronExpression是关键，如果可以动态设置cronExpression的值，也就说如果我们可以直接调用CronTriggerBean中设置cronExpression的方法，就可以顺利解决问题了。

熟悉1的朋友可以跳过不看，下面2、3是动态定时任务的具体实现。

 

1． Quartz在Spring中的简单配置

Spring配置文件：

    <bean id="schedulerJobDetail" class="org.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean">

        <property name="targetObject" ref="scheduleInfoAction"/>

        <property name="targetMethod" value="simpleJobTest"/>

        <property name="concurrent" value="false"/>

    </bean>

    <bean id="cronTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean" >

         <property name="jobDetail" ref="schedulerJobDetail"/>

         <property name="cronExpression">

             <value>0/10 * * * * ?</value>

         </property>

     </bean>

    <bean id="schedulerFactory" class="org.springframework.scheduling.quartz.SchedulerFactoryBean">

        <property name="triggers">

            <list>

                <ref local="cronTrigger"/>

            </list>

        </property>

</bean>

 

在上面的配置中设定了

① targetMethod: 指定需要定时执行scheduleInfoAction中的simpleJobTest()方法

② concurrent：对于相同的JobDetail，当指定多个Trigger时, 很可能第一个job完成之前，第二个job就开始了。指定concurrent设为false，多个job不会并发运行，第二个job将不会在第一个job完成之前开始。

③ cronExpression：0/10 * * * * ?表示每10秒执行一次，具体可参考附表。

④ triggers：通过再添加其他的ref元素可在list中放置多个触发器。

 

scheduleInfoAction中的simpleJobTest()方法

注意：此方法没有参数，如果scheduleInfoAction有两个方法simpleJobTest()和simpleJobTest(String argument)，则spring只会去执行无参的simpleJobTest().

public void simpleJobTest() { 

        log.warn("uh oh, Job is scheduled !'" + "' Success...");

    }

 

2．Quartz在Spring中动态设置cronTrigger方法一

Spring配置文件：

<bean id="scheduleInfoAction" class="com.lively.happyoa.jobs.webapp.action.ScheduleInfoAction">

        <property name="scheduler" ref="schedulerFactory"/>

        <property name="scheduleInfoManager" ref="scheduleInfoManager"/>

    </bean>

    <bean id="schedulerJobDetail" class="org.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean">

        <property name="targetObject" ref="scheduleInfoAction"/>

        <property name="targetMethod" value="reScheduleJob"/>

        <property name="concurrent" value="false"/>

    </bean>

    <bean id="cronTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean" >

         <property name="jobDetail" ref="schedulerJobDetail"/>

         <property name="cronExpression">

             <value>0/10 * * * * ?</value>

         </property>

     </bean>

    <bean id="schedulerFactory" class="org.springframework.scheduling.quartz.SchedulerFactoryBean">

        <property name="triggers">

            <list>

                <ref local="cronTrigger"/>

            </list>

        </property>

</bean>

 

scheduleInfoAction中的reScheduleJob ()方法及相关方法

① reScheduleJob读取数据库，获得自定义定时器调度时间():

    private void reScheduleJob() throws SchedulerException, ParseException {

        // 运行时可通过动态注入的scheduler得到trigger

        CronTriggerBean trigger = (CronTriggerBean) scheduler.getTrigger(

                "cronTrigger", Scheduler.DEFAULT_GROUP);

        String dbCronExpression = getCronExpressionFromDB();

        String originConExpression = trigger.getCronExpression();

    // 判断从DB中取得的任务时间(dbCronExpression)和现在的quartz线程中的任务时间(originConExpression)是否相等

    // 如果相等，则表示用户并没有重新设定数据库中的任务时间，这种情况不需要重新rescheduleJob

        if(!originConExpression.equalsIgnoreCase(dbCronExpression)){

            trigger.setCronExpression(dbCronExpression);

            scheduler.rescheduleJob("cronTrigger", Scheduler.DEFAULT_GROUP, trigger);

        }

    // 下面是具体的job内容，可自行设置

    // executeJobDetail();

}

 

② getCronExpressionFromDB()：从数据库中获得dbCronExpression的具体代码，由于使用了scheduleInfoManager，所以要在定义相应的setter方法

    private String getCronExpressionFromDB(){

        String sql="from ScheduleInfo scheduleInfo where 1=1 ";

        sql=sql+" and scheduleInfo.infoId = '"+"1" + "'";

        List scheduleList = scheduleInfoManager.queryScheduleInListBySql(sql);

        ScheduleInfo scheduleInfo = (ScheduleInfo)scheduleList.get(0);

        String dbCronExpression = scheduleInfo.getCronExpression();

        return dbCronExpression;

}

 

③ 在spring配置文件的scheduleInfoAction配置了相应的property（scheduler/scheduleInfoManager）,要为其设置setter方法

    private Scheduler scheduler;

    // 设值注入，通过setter方法传入被调用者的实例scheduler

    public void setScheduler(Scheduler scheduler) {

        this.scheduler = scheduler;

    }

    private ScheduleInfoManager scheduleInfoManager;

    // 设值注入，通过setter方法传入被调用者的实例scheduleInfoManager

    public void setScheduleInfoManager(ScheduleInfoManager scheduleInfoManager){

        this.scheduleInfoManager = scheduleInfoManager;

    }

 

3． Quartz在Spring中动态设置cronTrigger方法二

在上面的2中我们可以看到，尽管已经可以动态进行rescheduleJob了，不过依然需要我们设置一个cronExpression，如果尝试一下拿掉spring配置中的

        <property name="cronExpression">

             <value>0/10 * * * * ?</value>

         </property>

则容器（如tomcat）启动时会报错。

实际中我们希望tomcat启动时就可以直接去读数据库，拿到相应的dbCronExpression，然后定时执行一个job，而不希望配置初始的cronExpression ，观察下面的CronTriggerBean，考虑到cronExpression需要初始化，如果设定一个类InitializingCronTrigger继承CronTriggerBean，然后在这个类中做一些读取DB的初始化工作（设置cronExpression），问题就可以解决了。

 

Spring配置文件：

<bean id="scheduleInfoAction" class="com.lively.happyoa.jobs.webapp.action.ScheduleInfoAction">

        <property name="scheduler" ref="schedulerFactory"/>

        <property name="scheduleInfoManager" ref="scheduleInfoManager"/>

    </bean>

    <bean id="schedulerJobDetail" class="org.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean">

        <property name="targetObject" ref="scheduleInfoAction"/>

        <property name="targetMethod" value="reScheduleJob"/>

        <property name="concurrent" value="false"/>

    </bean>

    <bean id="cronTrigger" class="com.lively.happyoa.jobs.webapp.action.ScheduleInfoAction.InitializingCronTrigger">

         <property name="jobDetail" ref="schedulerJobDetail"/>

         <!--<property name="cronExpression">

             <value>0/10 * * * * ?</value>

         </property>-->

         <property name="scheduleInfoManager" ref="scheduleInfoManager"/>

     </bean>

    <bean id="schedulerFactory" class="org.springframework.scheduling.quartz.SchedulerFactoryBean">

        <property name="triggers">

            <list>

                <ref local="cronTrigger"/>

            </list>

        </property>

</bean>

 

InitializingCronTrigger中的相关方法

注意：在注入scheduleInfoManager属性的时候，我们可以去读取DB任务时间（之所以放在setter方法中，是因为需要在设置scheduleInfoManager后进行getCronExpressionFromDB()，否则，也可以①②逻辑把放在类的构造函数中）.

注意InitializingCronTrigger必须extends CronTriggerBean.

 

public class InitializingCronTrigger extends CronTriggerBean implements Serializable {

    private ScheduleInfoManager scheduleInfoManager;

    // 设值注入，通过setter方法传入被调用者的实例scheduleInfoManager

    public void setScheduleInfoManager(ScheduleInfoManager scheduleInfoManager){

        this.scheduleInfoManager = scheduleInfoManager;

        // 因为在getCronExpressionFromDB使用到了scheduleInfoManager，所以

        // 必须上一行代码设置scheduleInfoManager后进行getCronExpressionFromDB

        String cronExpression = getCronExpressionFromDB ();   // ①

        // 因为extends CronTriggerBean ，此处调用父类方法初始化cronExpression

        setCronExpression(cronExpression);                    // ②

}

    private String getCronExpressionFromDB(){

        String sql="from ScheduleInfo scheduleInfo where 1=1 ";

        sql=sql+" and scheduleInfo.infoId = '"+"1" + "'";

        List scheduleList = scheduleInfoManager.queryScheduleInListBySql(sql);

        ScheduleInfo scheduleInfo = (ScheduleInfo)scheduleList.get(0);

        String dbCronExpression = scheduleInfo.getCronExpression();

        return dbCronExpression;

 }

……

}

 

 

附表CronTrigger Expression(来自http://quartz.sourceforge.net/javadoc/org/quartz/CronTrigger.html)

Expression	Meaning
"0 0 12 * * ?"	Fire at 12pm (noon) every day
"0 15 10 ? * *"	Fire at 10:15am every day
"0 15 10 * * ?"	Fire at 10:15am every day
"0 15 10 * * ? *"	Fire at 10:15am every day
"0 15 10 * * ? 2005"	Fire at 10:15am every day during the year 2005
"0 * 14 * * ?"	Fire every minute starting at 2pm and ending at 2:59pm, every day
"0 0/5 14 * * ?"	Fire every 5 minutes starting at 2pm and ending at 2:55pm, every day
"0 0/5 14,18 * * ?"	Fire every 5 minutes starting at 2pm and ending at 2:55pm, AND fire every 5 minutes starting at 6pm and ending at 6:55pm, every day
"0 0-5 14 * * ?"	Fire every minute starting at 2pm and ending at 2:05pm, every day
"0 10,44 14 ? 3 WED"	Fire at 2:10pm and at 2:44pm every Wednesday in the month of March.
"0 15 10 ? * MON-FRI"	Fire at 10:15am every Monday, Tuesday, Wednesday, Thursday and Friday
"0 15 10 15 * ?"	Fire at 10:15am on the 15th day of every month
"0 15 10 L * ?"	Fire at 10:15am on the last day of every month
"0 15 10 ? * 6L"	Fire at 10:15am on the last Friday of every month
"0 15 10 ? * 6L"	Fire at 10:15am on the last Friday of every month
"0 15 10 ? * 6L 2002-2005"	Fire at 10:15am on every last friday of every month during the years 2002, 2003, 2004 and 2005
"0 15 10 ? * 6#3"	Fire at 10:15am on the third Friday of every month