Exploring Quartz Scheduler quartz-scheduler

1. Exploring Quartz Schedulerhttp://quartz-scheduler.org Orlando Java User Group Zemian Deng 2011.04.28

2. Agenda (1.5 hours) • Introduction (5 mins) • Scheduling Jobs (20 mins) • How job is stored and executed (15 mins) • Scheduler Deployment (20 mins) • Tips for working with quartz API (5 mins) • QA session (25 mins)

3. Introduction: What is Quartz • Fancier java.util.Timer • Unix CRON replacement • A rich API set to the scheduler • Job data persistence • Job executions control

4. Creating A Job Class public class SimpleJob implements org.quartz.Job { @Override public void execute(JobExecutionContextctx) throws JobExecutionException { System.out.println(“job is running”); } }

5. Scheduling One Time Job import org.quartz.JobDetail; import org.quartz.Scheduler; import org.quartz.SimpleTrigger; import org.quartz.impl.StdSchedulerFactory; public class QuartzExample { public static void main(String[] args) throws Exception { Scheduler scheduler = StdSchedulerFactory.getDefaultScheduler(); JobDetail job = new JobDetail("job1", SimpleJob.class); SimpleTrigger trigger = new SimpleTrigger("job1"); scheduler.scheduleJob(job, trigger); scheduler.start(); Thread.sleep(3000L); } }

6. More Scheduling Job Examples • One time job with startTime • Repeat job now • Repeat job with startTime • Repeat job forever • Cron job

7. Introduction: Quartz 2.0 vs 1.8 • Released in March 2011 • New API • Java DSL for creating jobs • Database schema changes http://quartz-scheduler.org/docs/2.0/newInQuartz2.html

8. Job Storages • In Memory Job Storage - RAMJobStore • JDBC Job Storage - JobStoreTX • TxDataSource Job Storage - JobStoreCMT • Spring TxDataSource Job Storage - LocalDataSourceJobStore

9. Quartz Scheduler Deployment • Standalone single JVM/Quartz scheduler • Server/Client based via RMI registry • Web Container single JVM/Quartz scheduler • Allow http client to interact with scheduler! • Clustering Quartz scheduler servers

10. Scheduler Tips #1 SimpleTrigger • Total Run Count = RepeatCount - 1 • You able to specify an end date regardless of repeatCount. • Trigger is NOT sensitive to Daylight Saving Time (DST).

11. Scheduler Tips #2 CronTrigger • Cron Expression has 6 + 1 optional fields. • Finest field unit is in second. • Trigger is senstive to DST. • Day-Of-Week starts with 1=SUN • You are allow only one Nth day-of-week (‘#’).

12. Scheduler Tips #3 Tired of java.util.Calendar& java.util.Date? Use org.quartz.TriggerUtils or Apache commons-langsDateUtils

13. Scheduler Tips #4 Spring Quartz Scheduler • You can’t disable auto shutdown! • The dataSource can partake Spring Tx Manager Abstraction. • Job may have access to Spring App Context through the Scheduler’s Context space.

14. Scheduler Tips #5 When using RMI server mode, there is a bug that can crash your scheduler: http://jira.terracotta.org/jira/browse/QTZ-135

15. Questions?