【原创】Quartz代码详解
阅读目录
简单介绍
在实际编程中，咱们常常会遇到定时任务，或是隔一段时间执行指定任务，例如：
1. 在每个月的30号9:00统计人员出勤状况；
2. 每隔10分钟执行一次入库操做；
上面的例子中，须要执行的操做就是Job（做业），而在指定时间或者间隔固定时间去触发这个Job的就是Trigger（触发器），而把两者联系在一块儿的就是Scheduler（调度器）；
Quartz主要要理解三个方面：
- Scheduler：调度器，将Job和Trigger关联起来；
- Job ：须要执行的做业；
- Trigger ：触发器，指定执行的时间，主要包括两种方式：
<1>指定时间：如每个月15号9:00，或者天天的12:00等等；
<2>间隔时间：如每隔10分钟执行一次，每隔2h执行一次等等；
1、Quartz简单实例
下面给出一个简单的示例：
SchedulerFactory schedFact = new org.quartz.impl.StdSchedulerFactory();
Scheduler sched = schedFact.getScheduler();
sched.start();
// define the job and tie it to our HelloJob class
JobDetail job = newJob(HelloJob.class)
.withIdentity("myJob", "group1")
.build();
// Trigger the job to run now, and then every 40 seconds
trigger = newTrigger()
.withIdentity("myTrigger", "group1")
.startNow()
.withSchedule(simpleSchedule()
.withIntervalInSeconds(40)
.repeatForever())
.build();
// Tell quartz to schedule the job using our trigger
sched.scheduleJob(job, trigger);
下面的截图是Java源码给出的示例：
咱们在使用Quartz时，通常的操做步骤为：
步骤1：自定义Job类（如：MyJob），实现Job接口；
步骤2：使用
JobBuilder生成JobDetail；
步骤3：定义Trigger类，通常使用TriggerBuilder生成；
步骤4：定义Scheduler类，使用
Scheduler .
scheduleJob(job, trigger)将job和trigger进行关联;
步骤5：
Scheduler.start();
步骤6：当须要关闭
Scheduler
时，使用
Scheduler.
shutdown();
下面将具体进行讲解。
2、Job、JobDetail、JobBuilder
官方定义：
- Job - an interface to be implemented by components that you wish to have executed by the scheduler.
- JobDetail - used to define instances of Jobs.
- JobBuilder - used to define/build JobDetail instances, which define instances of Jobs.
Job
Job是一个接口类，下面是它的源码：
若是要实现本身的做业（任务），最简单的方式就是实现该接口，并实现接口中的execute()方法，当触发该做业时，就是执行execute()方法；
public class HelloJob implements Job {
public HelloJob() {
}
public void execute(JobExecutionContext context)
throws JobExecutionException
{
System.err.println("Hello! HelloJob is executing.");
}
}
JobDetail
JobDetail ：用于定义Job的实例，通常该类都是经过JobBuilder生成；
JobBuilder：
用于定义或建立JobDetail实例，使用了建造者模式；
JobDetail job = newJob(HelloJob.class)
.withIdentity("myJob", "group1") // name "myJob", group "group1"
.build();
//带参数
JobDetail job = JobBuilder.newJob(clazz)
.withIdentity(new JobKey(jobName, groupName))
.usingJobData(new JobDataMap(params))
.build();
从上面的接口类中咱们能够知道，只要有了JobDetail的实现类，咱们就能够获取到：
- key;
- JobClass；
- JobDataMap；等
那咱们在自定义的Job中怎么才能获取到JobDetail相关信息呢？
由上面可知，当自定义的做业被触发时，咱们能够经过JobExecutionContext获取到JobDetail，进而获取JobDataMap、JobKey、JobClass等等信息；
JobBuilder
这里JobBuilder使用了建造者模式，下面对其源码进行解析；
对于建造者模式，这里不进行详述，首先看下它的字段：
JobKey:做业的惟一标识，由name和group组成，以下：
jobClass：指定上述咱们讲的自定义的Job（如：HelloJob ）；
JobDataMap：能够经过这个属性给自定义的Job（如：HelloJob）传递参数；
由于使用了建造者模式，因此实际建立的对象为：JobDetailImpl
JobDetailImpl类实现了JobDeteil接口，以下：
下图是类的层级结构图：
3、Trigger、TriggerBuilder
官方定义：
Trigger - a component that defines the schedule upon which a given Job will be executed.
TriggerBuilder - used to define/build Trigger instances.
下面是触发器层次结构，经常使用的有SimpleTrigger、CronTrigger等；
SimpleTrigger
主要属性：
CronTrigger
使用CronTrigger能够进行很强大的控制，关于Cron表达式，下面的章节会介绍；
主要的参数：
TriggerBuilder
首先看下实现的例子：使用的也是建造者模式（建造者模式可自行搜索）；
TriggerBuilder的属性以下：
经过withIdentity()方法设定trigger惟一标识：
经过forJob()方法将Trigger和指定的Job绑定
前面咱们已经知道：
- 在使用JobBuilder建立JobDetail时，经过方法withIdentity()指定了JobDetail的JobKey；
- 这里经过TriggerBuilder的forJob()一样指定了JobKey；
==>只要上面两个JobKey设置的相同，则JobDetail和Trigger便绑定在一块儿了；
后面只须要使用Scheduler.scheduleJob(job,trigger)进行调度便可；
经过方法withSchedule设置调度器：
从上面能够看出，这个方法传递进去的其实是一个调度器Scheduler的Builder，真正的调度器Scheduler仍是须要经过ScheduleBuilder去建立，这里使用的仍是建造者模式，从下面的层次能够看出，已经实现了4种ScheduleBuilder，这里以SimplesCheduleBuilder进行分析，其余相似
下面咱们看看SimplesCheduleBuilder的源码实现；
上面是build方法，能够看出，真正建立的是：SimpleTriggerImpl类，这个类在上面已经介绍过，它是Trigger的一个实现类；
咱们接着看TriggerBuilder的build方法：
4、Scheduler
官方定义：
Scheduler - the main API for interacting with the scheduler.
与调度程序交互的主要API。
具体实现类：
主要的方法：
Scheduler scheduler = StdSchedulerFactory.getDefaultScheduler();scheduler.schedeleJob(Job,trigger)scheduler.start();scheduler.shutdown();
说明：
只有在scheduler.start();以后，trigger以及Job才能有效运行；
shutdown用于关闭；
schedeleJob方法介绍
// Tell quartz to schedule the job using our trigger
sched.scheduleJob(job, trigger);
官方介绍以下：
如今以StdScheduler做为示例进行介绍：
start()方法介绍
使用start()方法来激活Trigger，执行定时任务；
示例：
* ("all values") - used to select all values within a field. For example, "" in the minute field means *"every minute".java
? ("no specific value") - useful when you need to specify something in one of the two fields in which the character is allowed, but not the other. For example, if I want my trigger to fire on a particular day of the month (say, the 10th), but don't care what day of the week that happens to be, I would put "10" in the day-of-month field, and "?" in the day-of-week field. See the examples below for clarification.express
- - used to specify ranges. For example, "10-12" in the hour field means "the hours 10, 11 and 12".编程
, - used to specify additional values. For example, "MON,WED,FRI" in the day-of-week field means "the days Monday, Wednesday, and Friday".windows
/ - used to specify increments. For example, "0/15" in the seconds field means "the seconds 0, 15, 30, and 45". And "5/15" in the seconds field means "the seconds 5, 20, 35, and 50". You can also specify '/' after the '' character - in this case '' is equivalent to having '0' before the '/'. '1/3' in the day-of-month field means "fire every 3 days starting on the first day of the month".app
L ("last") - has different meaning in each of the two fields in which it is allowed. For example, the value "L" in the day-of-month field means "the last day of the month" - day 31 for January, day 28 for February on non-leap years. If used in the day-of-week field by itself, it simply means "7" or "SAT". But if used in the day-of-week field after another value, it means "the last xxx day of the month" - for example "6L" means "the last friday of the month". You can also specify an offset from the last day of the month, such as "L-3" which would mean the third-to-last day of the calendar month. When using the 'L' option, it is important not to specify lists, or ranges of values, as you'll get confusing/unexpected results.ide
W ("weekday") - used to specify the weekday (Monday-Friday) nearest the given day. As an example, if you were to specify "15W" as the value for the day-of-month field, the meaning is: "the nearest weekday to the 15th of the month". So if the 15th is a Saturday, the trigger will fire on Friday the 14th. If the 15th is a Sunday, the trigger will fire on Monday the 16th. If the 15th is a Tuesday, then it will fire on Tuesday the 15th. However if you specify "1W" as the value for day-of-month, and the 1st is a Saturday, the trigger will fire on Monday the 3rd, as it will not 'jump' over the boundary of a month's days. The 'W' character can only be specified when the day-of-month is a single day, not a range or list of days.ui
The 'L' and 'W' characters can also be combined in the day-of-month field to yield 'LW', which translates to *"last weekday of the month"*.
- # - used to specify "the nth" XXX day of the month. For example, the value of "6#3" in the day-of-week field means"the third Friday of the month" (day 6 = Friday and "#3" = the 3rd one in the month). Other examples: "2#1" = the first Monday of the month and "4#5" = the fifth Wednesday of the month. Note that if you specify "#5" and there is not 5 of the given day-of-week in the month, then no firing will occur that month.
7、程序示例
AbstractSchedule类：抽象基类
package com.sssppp.TimerSchedule.quartz.schedule;import java.util.Date;import java.util.Map;import java.util.Properties;import org.quartz.CronScheduleBuilder;import org.quartz.CronTrigger;import org.quartz.JobBuilder;import org.quartz.JobDataMap;import org.quartz.JobDetail;import org.quartz.JobKey;import org.quartz.Scheduler;import org.quartz.SchedulerException;import org.quartz.TriggerBuilder;import org.quartz.impl.StdSchedulerFactory;import com.sssppp.TimerSchedule.quartz.listeners.MyJobListener;import com.sssppp.TimerSchedule.quartz.listeners.MySchedulerListener;import com.sssppp.TimerSchedule.quartz.listeners.MyTriggerListener;public abstract class AbstractSchedule { public Scheduler scheduler = null; private static final String JOB_GROUPNAME = "MY_JOB_GROUP"; private static final String TRIGGER_GROUPNAME = "MY_TRIGGER_GROUP"; /** * 初始化Scheduler，并添加Listeners */ public AbstractSchedule() { try { if (scheduler == null) { System.out.println("Begin init scheduler..."); try { Properties props = new Properties(); props.put(StdSchedulerFactory.PROP_THREAD_POOL_CLASS, "org.quartz.simpl.SimpleThreadPool"); props.put("org.quartz.threadPool.threadCount", "100");// 同时100个线程运行 props.put("org.quartz.jobStore.misfireThreshold", "180000");// trigger过时30分钟内还有效 StdSchedulerFactory factory = new StdSchedulerFactory(); factory.initialize(props); scheduler = factory.getScheduler(); } catch (SchedulerException e) { e.printStackTrace(); } scheduler.getListenerManager().addJobListener(new MyJobListener()); scheduler.getListenerManager().addSchedulerListener( new MySchedulerListener()); scheduler.getListenerManager().addTriggerListener( new MyTriggerListener()); } } catch (Exception e) { System.err.println("Init scheduler failed, error message :" + e); } } public abstract Scheduler handleJob(String jobName, String triggerName, String cronStr); @SuppressWarnings({ "unchecked", "rawtypes" }) public void scheduleJob(String jobName, String triggerName, String express, Class clazz) { JobDetail job = null; CronTrigger trigger = null; try { job = JobBuilder.newJob(clazz).withIdentity(jobName, JOB_GROUPNAME) .build(); trigger = TriggerBuilder.newTrigger() .withIdentity(triggerName, TRIGGER_GROUPNAME) .forJob(jobName, JOB_GROUPNAME) .withSchedule(CronScheduleBuilder.cronSchedule(express)) .build(); } catch (Exception e) { System.err.println("scheduler ParseException!" + e); } Date date = null; try { date = scheduler.scheduleJob(job, trigger); } catch (SchedulerException e) { System.err.println("scheduler SchedulerException!" + e); } System.out.println(job.getKey().toString() + " has been scheduled to run at: " + date + " and repeat based on expression: " + trigger.getCronExpression()); } /** * 建立Job和Trigger，并使用scheduler将job和Trigger进行关联 * * @param jobName * @param triggerName * @param express * :cronStr表达式 * @param clazz * ：job的class * @param params * ：Job使用的参数 */ @SuppressWarnings({ "unchecked", "rawtypes" }) public void scheduleJobWithParams(String jobName, String triggerName, String express, Class clazz, Map<String, Object> params) { JobDetail job = null; CronTrigger trigger = null; try { job = JobBuilder.newJob(clazz) .withIdentity(new JobKey(jobName, JOB_GROUPNAME)) .usingJobData(new JobDataMap(params)).build(); trigger = TriggerBuilder.newTrigger() .withIdentity(triggerName, TRIGGER_GROUPNAME) .forJob(jobName, JOB_GROUPNAME) .withSchedule(CronScheduleBuilder.cronSchedule(express)) .build(); } catch (Exception e) { System.err.println("scheduler ParseException!" + e); } Date date = null; try { date = scheduler.scheduleJob(job, trigger); } catch (SchedulerException e) { System.err.println("scheduler SchedulerException!" + e); } System.out.println(job.getKey().toString() + " has been scheduled to run at: " + date + " and repeat based on expression: " + trigger.getCronExpression()); } /** * Starts the Scheduler's threads that fire Triggers */ public void startJob() { try { this.scheduler.start(); } catch (SchedulerException e) { System.err.println("trigger job error!" + e); } } public boolean stopJob(String jobName) { boolean b = false; JobKey jobkey = new JobKey(jobName, JOB_GROUPNAME); try { if (this.scheduler.checkExists(jobkey)) { b = this.scheduler.deleteJob(jobkey); System.out.println("Stop Job[" + jobName + "] success."); } } catch (SchedulerException e) { System.err.println("Stop job fail."); e.printStackTrace(); } return b; } public void shutdownScheduler() { try { this.scheduler.shutdown(true); System.out.println("Shutdown scheduler success."); } catch (SchedulerException e) { System.err.println("Shutdown Scheduler fail."); e.printStackTrace(); } }}
MyJobSchedule.java
package com.sssppp.TimerSchedule.quartz.schedule;import java.util.HashMap;import java.util.Map;import org.quartz.Scheduler;import com.sssppp.TimerSchedule.quartz.Jobs.MyJob;public class MyJobSchedule extends AbstractSchedule { private static MyJobSchedule myJobSchedule = new MyJobSchedule(); private MyJobSchedule() { } public static MyJobSchedule getInstance() { return myJobSchedule; } @Override public Scheduler handleJob(String jobName, String triggerName, String cronStr) { Map<String, Object> params = new HashMap<String, Object>(); params.put(MyJob.JOB_PARAM_KEY, "This is myJob param"); scheduleJobWithParams(jobName, triggerName, cronStr, MyJob.class, params); startJob(); return this.scheduler; }}
MyJob.java
package com.sssppp.TimerSchedule.quartz.Jobs;import java.util.Date;import org.quartz.Job;import org.quartz.JobExecutionContext;import org.quartz.JobExecutionException;import com.ibm.icu.text.SimpleDateFormat;public class MyJob implements Job { public final static String JOB_PARAM_KEY = "jobParam"; @Override public void execute(JobExecutionContext jobexecutioncontext) throws JobExecutionException { SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); // 获取传递给Job的参数 String param = (String) jobexecutioncontext.getJobDetail() .getJobDataMap().get(JOB_PARAM_KEY); System.out.println("Now exec MyJob,param【" + param + "】, time:" + sdf.format(new Date())); }}
QuartzManager.java
package com.sssppp.TimerSchedule.quartz;import com.sssppp.TimerSchedule.quartz.schedule.MyJobSchedule;public class QuartzManager { private static final QuartzManager quartzManager = new QuartzManager(); private static final String MY_JOB_NAME = "MY_JOB_NAME"; private static final String MY_TRIGGER_NAME = "MY_TRIGGER_NAME"; private static final String MY_JOB_CRONSTR = "0/5 * * * * ?"; private QuartzManager() { } public static QuartzManager getInstance() { return quartzManager; } public void startMyJob() { MyJobSchedule.getInstance().handleJob(MY_JOB_NAME, MY_TRIGGER_NAME, MY_JOB_CRONSTR); } public void stopMyJobAndShutdownScheduler() { MyJobSchedule.getInstance().stopJob(MY_JOB_NAME); MyJobSchedule.getInstance().shutdownScheduler(); }}
TestCase.java
package com.sssppp.TimerSchedule.quartz;public class TestCase { @SuppressWarnings("static-access") public static void main(String[] args) throws InterruptedException { QuartzManager.getInstance().startMyJob(); Thread.currentThread().sleep(12 * 1000); QuartzManager.getInstance().stopMyJobAndShutdownScheduler(); }}
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