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
|