Quartz在Spring中动态设置cronExpression

时间:2024-01-08 13:06:38
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