How is this Quartz Cron Expression executed

Question

I have a the following;

private String cronExpression = "";
private final String jobID = "MyJObID";
...
Scheduler scheduler = ServiceLocator.getInstance().getScheduler();
CronTrigger trigger = new CronTrigger(jobID , Scheduler.DEFAULT_GROUP, cronExpression);
JobDetail jobDetail = new JobDetail(jobID , Scheduler.DEFAULT_GROUP, MyJob.class);
scheduler.scheduleJob(jobDetail, trigger);

My question is when is this job triggered for the empty cron expression?

Answer 1

Thanks for the help guys, found the issue.

After some night of searching i found out that the class was registered in JBoss as a MBean and a value for the cron expression attribute was set to some meaningful value in the deployment descriptor

Sigh

Answer 2

Are you sure it works?

Just by looking at the org.quartz.CronExpression#buildExpression() method code it looks like an exception should be thrown:

        if (exprOn <= DAY_OF_WEEK) {
            throw new ParseException("Unexpected end of expression.",
                        expression.length());
        }

      // exprOn should be equal to SECOND in case of empty String given

[checked in Quartz 1.6.0]