什么是動(dòng)態(tài)定時(shí)任務(wù)：是由客戶制定生成的，服務(wù)端只知道該去執(zhí)行什么任務(wù)，但任務(wù)的定時(shí)是不確定的（是由客戶制定）。
這樣總不能修改配置文件每定制個(gè)定時(shí)任務(wù)就增加一個(gè)trigger吧，即便允許客戶修改配置文件，但總需要重新啟動(dòng)web服務(wù)啊，研究了下Quartz在Spring中的動(dòng)態(tài)定時(shí)，發(fā)現(xiàn)<bean id="cronTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean" >
<property name="jobDetail" ref="schedulerJobDetail"/>
<property name="cronExpression">
<value>0/10 * * * * ?</value>
</property>
中cronExpression是關(guān)鍵，如果可以動(dòng)態(tài)設(shè)置cronExpression的值，也就說(shuō)如果我們可以直接調(diào)用CronTriggerBean中設(shè)置cronExpression的方法，就可以順利解決問(wèn)題了。
熟悉1的朋友可以跳過(guò)不看，下面2、3是動(dòng)態(tài)定時(shí)任務(wù)的具體實(shí)現(xiàn)。
1． Quartz 在Spring中的簡(jiǎn)單配置
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>
在上面的配置中設(shè)定了
① targetMethod: 指定需要定時(shí)執(zhí)行scheduleInfoAction中的simpleJobTest()方法
② concurrent：對(duì)于相同的JobDetail，當(dāng)指定多個(gè)Trigger時(shí), 很可能第一個(gè)job完成之前，第二個(gè)job就開(kāi)始了。指定concurrent設(shè)為false，多個(gè)job不會(huì)并發(fā)運(yùn)行，第二個(gè)job將不會(huì)在第一個(gè)job完成之前開(kāi)始。
③ cronExpression：0/10 * * * * ?表示每10秒執(zhí)行一次，具體可參考附表。
④ triggers：通過(guò)再添加其他的ref元素可在list中放置多個(gè)觸發(fā)器。
scheduleInfoAction 中的simpleJobTest()方法
注意：此方法沒(méi)有參數(shù)，如果scheduleInfoAction有兩個(gè)方法simpleJobTest()和simpleJobTest(String argument)，則spring只會(huì)去執(zhí)行無(wú)參的simpleJobTest().
public void simpleJobTest() {
log.warn("uh oh, Job is scheduled !'" + "' Success...");
}
2 ．Quartz在Spring中動(dòng)態(tài)設(shè)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 ()方法及相關(guān)方法
① reScheduleJob():讀取數(shù)據(jù)庫(kù)，獲得自定義定時(shí)器調(diào)度時(shí)間
private void reScheduleJob() throws SchedulerException, ParseException {
// 運(yùn)行時(shí)可通過(guò)動(dòng)態(tài)注入的scheduler得到trigger
CronTriggerBean trigger = (CronTriggerBean) scheduler.getTrigger(
"cronTrigger", Scheduler.DEFAULT_GROUP);
String dbCronExpression = getCronExpressionFromDB();
String originConExpression = trigger.getCronExpression();
// 判斷從DB中取得的任務(wù)時(shí)間(dbCronExpression)和現(xiàn)在的quartz線程中的任務(wù)時(shí)間(originConExpression)是否相等
// 如果相等，則表示用戶并沒(méi)有重新設(shè)定數(shù)據(jù)庫(kù)中的任務(wù)時(shí)間，這種情況不需要重新rescheduleJob
if(!originConExpression.equalsIgnoreCase(dbCronExpression)){
trigger.setCronExpression(dbCronExpression);
scheduler.rescheduleJob("cronTrigger", Scheduler.DEFAULT_GROUP, trigger);
}
// 下面是具體的job內(nèi)容，可自行設(shè)置
// executeJobDetail();
}
② getCronExpressionFromDB()：從數(shù)據(jù)庫(kù)中獲得dbCronExpression的具體代碼，由于使用了scheduleInfoManager，所以要在定義相應(yīng)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配置了相應(yīng)的property（scheduler/scheduleInfoManager）,要為其設(shè)置setter方法
private Scheduler scheduler;
// 設(shè)值注入，通過(guò)setter方法傳入被調(diào)用者的實(shí)例scheduler
public void setScheduler(Scheduler scheduler) {
this.scheduler = scheduler;
}
private ScheduleInfoManager scheduleInfoManager;
// 設(shè)值注入，通過(guò)setter方法傳入被調(diào)用者的實(shí)例scheduleInfoManager
public void setScheduleInfoManager(ScheduleInfoManager scheduleInfoManager){
this.scheduleInfoManager = scheduleInfoManager;
}
3． Quartz 在Spring中動(dòng)態(tài)設(shè)置cronTrigger方法二
在上面的2中我們可以看到，盡管 已經(jīng)可以動(dòng)態(tài)進(jìn)行 rescheduleJob 了，不過(guò)依然需要我們?cè)O(shè)置一個(gè) cronExpression ，如果嘗試一下拿掉spring配置中的
<property name="cronExpression">
<value>0/10 * * * * ?</value>
</property>
則容器（如tomcat）啟動(dòng)時(shí)會(huì)報(bào)錯(cuò)。
實(shí)際中我們希望tomcat啟動(dòng)時(shí)就可以直接去讀數(shù)據(jù)庫(kù)，拿到相應(yīng)的 dbCronExpression ，然后定時(shí)執(zhí)行一個(gè)job，而不希望配置初始的 cronExpression ，觀察下面的 CronTriggerBean ，考慮到cronExpression需要初始化，如果設(shè)定一個(gè)類InitializingCronTrigger繼承CronTriggerBean，然后在這個(gè)類中做一些讀取DB的初始化工作（設(shè)置cronExpression），問(wèn)題就可以解決了。
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 中的相關(guān)方法
注意：在注入scheduleInfoManager屬性的時(shí)候，我們可以去讀取DB任務(wù)時(shí)間（之所以放在setter方法中，是因?yàn)樾枰谠O(shè)置scheduleInfoManager后進(jìn)行getCronExpressionFromDB()，否則，也可以①②邏輯把放在類的構(gòu)造函數(shù)中）.
注意InitializingCronTrigger必須extendsCronTriggerBean.
public class InitializingCronTrigger extendsCronTriggerBean implements Serializable {
private ScheduleInfoManager scheduleInfoManager;
// 設(shè)值注入，通過(guò)setter方法傳入被調(diào)用者的實(shí)例scheduleInfoManager
public void setScheduleInfoManager(ScheduleInfoManager scheduleInfoManager){
this.scheduleInfoManager = scheduleInfoManager;
// 因?yàn)樵?span style="background: silver">getCronExpressionFromDB使用到了scheduleInfoManager，所以
// 必須上一行代碼設(shè)置scheduleInfoManager后進(jìn)行getCronExpressionFromDB
String cronExpression = getCronExpressionFromDB (); // ①
// 因?yàn)?span style="color: fuchsia">extendsCronTriggerBean ，此處調(diào)用父類方法初始化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( 來(lái)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
|
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