Quartz Scheduler Example Programs and Sample Code : The Quartz Example Programs : Example 3 - Cron-based Triggers
Example 3 - Cron-based Triggers
This example is designed to demonstrate how you can use CronTriggers to schedule jobs. This example will fire off several simple jobs that say "Hello World" and display the date and time that the job was executed.
The program will perform the following actions:
*Start up the Quartz Scheduler
*Schedule several jobs using various features of CronTrigger
*Wait for 300 seconds (5 minutes) to give Quartz a chance to run the jobs
*Shut down the scheduler
Note:  
Refer to the Quartz Javadoc for a thorough explanation of CronTrigger.
Running the Example
This example can be executed from the examples/example3 directory. There are two ways to run this example
*example3.sh - A UNIX/Linux shell script
*example3.bat - A Windows batch file
The Code
The code for this example resides in the package org.quartz.examples.example3.
The code in this example is made up of the following classes:
Class Name
Description
CronTriggerExample
The main program.
SimpleJob
A simple job that says Hello World and displays the date/time.
SimpleJob
SimpleJob is a simple job that implements the Job interface and logs a message to the log (by default, this will simply go to the screen). The current date and time is printed in the job so that you can see exactly when the job was executed.
public void execute(JobExecutionContext context) throws JobExecutionException {
JobKey jobKey = context.getJobDetail().getKey();
_log.info("SimpleJob says: " + jobKey + " executing at " + new Date());
}
CronTriggerExample
The program starts by getting an instance of the Scheduler. This is done by creating a StdSchedulerFactory and then using it to create a scheduler. This will create a simple, RAM-based scheduler.
SchedulerFactory sf = new StdSchedulerFactory();
Scheduler sched = sf.getScheduler();
Job #1 is scheduled to run every 20 seconds
JobDetail job = newJob(SimpleJob.class)
.withIdentity("job1", "group1")
.build();
CronTrigger trigger = newTrigger()
.withIdentity("trigger1", "group1")
.withSchedule(cronSchedule("0/20 * * * * ?"))
.build();
sched.scheduleJob(job, trigger);
Job #2 is scheduled to run every other minute starting at 15 seconds past the minute.
job = newJob(SimpleJob.class)
.withIdentity("job2", "group1")
.build();
trigger = newTrigger()
.withIdentity("trigger2", "group1")
.withSchedule(cronSchedule("15 0/2 * * * ?"))
.build();
sched.scheduleJob(job, trigger);
Job #3 is scheduled to run every other minute between 8am and 5pm (17 :00).
job = newJob(SimpleJob.class)
.withIdentity("job3", "group1")
.build();
trigger = newTrigger()
.withIdentity("trigger3", "group1")
.withSchedule(cronSchedule("0 0/2 8-17 * * ?"))
.build();
sched.scheduleJob(job, trigger);
Job #4 is scheduled to run every three minutes, but only between 5pm and 11pm
job = newJob(SimpleJob.class)
.withIdentity("job4", "group1")
.build();
trigger = newTrigger()
.withIdentity("trigger4", "group1")
.withSchedule(cronSchedule("0 0/3 17-23 * * ?"))
.build();
sched.scheduleJob(job, trigger);
Job #5 is scheduled to run at 10am on the 1st and 15th days of the month
job = newJob(SimpleJob.class)
.withIdentity("job5", "group1")
.build();
trigger = newTrigger()
.withIdentity("trigger5", "group1")
.withSchedule(cronSchedule("0 0 10am 1,15 * ?"))
.build();
sched.scheduleJob(job, trigger);
Job #6 is scheduled to run every 30 seconds on weekdays (Monday through Friday)
job = newJob(SimpleJob.class)
.withIdentity("job6", "group1")
.build();
trigger = newTrigger()
.withIdentity("trigger6", "group1")
.withSchedule(cronSchedule("0,30 * * ? * MON-FRI"))
.build();
sched.scheduleJob(job, trigger);
Job #7 is scheduled to run every 30 seconds on weekends (Saturday and Sunday)
job = newJob(SimpleJob.class)
.withIdentity("job7", "group1")
.build();
trigger = newTrigger()
.withIdentity("trigger7", "group1")
.withSchedule(cronSchedule("0,30 * * ? * SAT,SUN"))
.build();
sched.scheduleJob(job, trigger);
The scheduler is then started (it also would have been fine to start it before scheduling the jobs).
sched.start();
To let the scheduler have an opportunity to run the job, our program sleeps for five minutes (300 seconds). The scheduler is running in the background and should fire off several jobs during that time.
Note:  
Because many of the jobs have hourly and daily restrictions on them, not all of the jobs will run in this example. For example: Job #6 only runs on weekdays while Job #7 only runs on weekends.
Thread.sleep(300L * 1000L);
Finally, the program gracefully shuts down the scheduler:
sched.shutdown(true);
Note:  
Passing "true" into the shutdown() method tells the Quartz Scheduler to wait until all jobs have completed running before returning from the method call.
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