Scheduler 每次执行，都会根据JobDetail创建一个新的Job实例，这样就可以规避并发访问的问题（jobDetail的实例也是新的）
Quzrtz 定时任务默认都是并发执行，不会等待上一次任务执行完毕，只要间隔时间到就会执行，如果定时任务执行太长，会长时间占用资源，导致其它任务堵塞
@DisallowConcurrentExecution: job类上，禁止并发地执行同一个job定义 (JobDetail定义的)的多个实例。
- scheduler：可以理解为定时任务的工作容器或者说是工作场所，所有定时任务都是放在里面工作，可以开启和停止。
- trigger：可以理解为是定时任务任务的工作规则配置，例如说，没个几分钟调用一次，或者说指定每天那个时间点执行。
- jobDetail：定时任务的信息，例如配置定时任务的名字，群组之类的。
- job：定时任务的真正的业务处理逻辑的地方。
简单示例
TestClient.Java
import org.quartz.*;import org.quartz.impl.StdSchedulerFactory;public class TaskClient { public static void main(String[] args) { JobDetail jobDetail = JobBuilder.newJob(TaskJob.class) .withIdentity("job1", "group1") //设置JOB的名字和组 .build(); Trigger trigger = TriggerBuilder.newTrigger() .withIdentity("trigger1", "trigger1") .startNow() .withSchedule(SimpleScheduleBuilder.simpleSchedule().withIntervalInSeconds(1) .repeatForever()) .build(); try { Scheduler scheduler = StdSchedulerFactory.getDefaultScheduler(); scheduler.scheduleJob(jobDetail,trigger); scheduler.start(); } catch (SchedulerException ex) { ex.printStackTrace(); } }}TaskJob.Java
import cn.hutool.core.date.DateUtil;import org.quartz.Job;import org.quartz.JobExecutionContext;import org.quartz.JobExecutionException;public class TaskJob implements Job { @Override public void execute(JobExecutionContext jobExecutionContext) throws JobExecutionException { System.out.println("TaskJob => " + DateUtil.now()); }}
usingJobData
通过 usingJobData 往定时任务中传递参数
import org.quartz.*;import org.quartz.impl.StdSchedulerFactory;public class TaskClient { public static void main(String[] args) { JobDetail jobDetail = JobBuilder.newJob(TaskJob.class) .withIdentity("job1", "group1") .usingJobData("job","jobDetail1.JobDataMap.Value") .build(); Trigger trigger = TriggerBuilder.newTrigger() .withIdentity("trigger1", "trigger1") .usingJobData("trigger","trigger.JobDataMap.Value") .startNow() .withSchedule(SimpleScheduleBuilder.simpleSchedule().withIntervalInSeconds(1) .repeatForever()) .build(); try { Scheduler scheduler = StdSchedulerFactory.getDefaultScheduler(); scheduler.scheduleJob(jobDetail,trigger); scheduler.start(); } catch (SchedulerException ex) { ex.printStackTrace(); } }}TaskJob.java
import org.quartz.Job;import org.quartz.JobDataMap;import org.quartz.JobExecutionContext;import org.quartz.JobExecutionException;public class TaskJob implements Job { @Override public void execute(JobExecutionContext context) throws JobExecutionException { JobDataMap jobDataMap = context.getJobDetail().getJobDataMap(); JobDataMap triggerMap = context.getTrigger().getJobDataMap(); JobDataMap mergeMap = context.getMergedJobDataMap(); System.out.println("jobDataMap => " + jobDataMap.getString("job")); System.out.println("triggerMap => " + triggerMap.getString("trigger")); System.out.println("mergeMap => " + mergeMap.getString("trigger")); }}
通过 属性赋值
import org.quartz.*;import org.quartz.impl.StdSchedulerFactory;public class TaskClient { public static void main(String[] args) { JobDetail jobDetail = JobBuilder.newJob(TaskJob.class) .withIdentity("job1", "group1") .usingJobData("job","jobDetail1.JobDataMap.Value") .usingJobData("name","jobDetail1.name.Value") //通过 setName 自动赋值 .build(); Trigger trigger = TriggerBuilder.newTrigger() .withIdentity("trigger1", "trigger1") .usingJobData("trigger","trigger.JobDataMap.Value") .usingJobData("name","trigger.name.Value") //如果 Trigger 有值，会覆盖 JobDetail .startNow() .withSchedule(SimpleScheduleBuilder.simpleSchedule().withIntervalInSeconds(1) .repeatForever()) .build(); try { Scheduler scheduler = StdSchedulerFactory.getDefaultScheduler(); scheduler.scheduleJob(jobDetail,trigger); scheduler.start(); } catch (SchedulerException ex) { ex.printStackTrace(); } }}import org.quartz.*;public class TaskJob implements Job { private String name; public void setName(String name) { this.name = name; } @Override public void execute(JobExecutionContext context) throws JobExecutionException { System.out.println("name => " + name); }}非并发执行
@DisallowConcurrentExecution job类上，禁止并发地执行同一个job定义 (JobDetail定义的)的多个实例。
import cn.hutool.core.date.DateUtil;import org.quartz.*;@DisallowConcurrentExecutionpublic class TaskJob implements Job { @Override public void execute(JobExecutionContext context) { System.out.println("Time => " + DateUtil.now()); try { Thread.sleep(3000); } catch (InterruptedException e) { e.printStackTrace(); } }}@PersistJobDataAfterExecution
持久化JobDetail中的JobDataMap（对 trigger 中的 datamap 无效），如果一个任务不是
import cn.hutool.core.date.DateUtil;import org.quartz.*;//持久化JobDetail中的JobDataMap（对 trigger 中的 datamap 无效），如果一个任务不是@PersistJobDataAfterExecutionpublic class TaskJob implements Job { @Override public void execute(JobExecutionContext context) { JobDataMap triggerMap = context.getJobDetail().getJobDataMap(); triggerMap.put("count", triggerMap.getInt("count") + 1); System.out.println("Time => " + DateUtil.now() + " count =>" + triggerMap.getInt("count")); }}Client
import org.quartz.*;import org.quartz.impl.StdSchedulerFactory;public class TaskClient { public static void main(String[] args) { JobDetail jobDetail = JobBuilder.newJob(TaskJob.class) .withIdentity("job1", "group1") .usingJobData("job","jobDetail1.JobDataMap.Value") .usingJobData("name","jobDetail1.name.Value") //通过 setName 自动赋值 .usingJobData("count",0) //通过 setName 自动赋值 .build(); Trigger trigger = TriggerBuilder.newTrigger() .withIdentity("trigger1", "trigger1") .usingJobData("trigger","trigger.JobDataMap.Value") .usingJobData("name","trigger.name.Value") //如果 Trigger 有值，会覆盖 JobDetail .startNow() .withSchedule(SimpleScheduleBuilder.simpleSchedule().withIntervalInSeconds(1) .repeatForever()) .build(); try { Scheduler scheduler = StdSchedulerFactory.getDefaultScheduler(); scheduler.scheduleJob(jobDetail,trigger); scheduler.start(); } catch (SchedulerException ex) { ex.printStackTrace(); } }}