quartz: preventing concurrent instances of a job in jobs.xml

Question

This should be really easy. I\'m using Quartz running under Apache Tomcat 6.0.18, and I have a jobs.xml file which sets up my scheduled job that runs every minute.

W

Answer 1

Slight variation to scaramouche's solution.

List<JobExecutionContext> jobs = jobExecutionContext.getScheduler().getCurrentlyExecutingJobs();
for (JobExecutionContext job : jobs) {
    if (job.getTrigger().equals(jobExecutionContext.getTrigger()) && !job.getFireInstanceId().equals(jobExecutionContext.getFireInstanceId()) {
        logger.info("There's another instance running, so leaving" + this);
        return;
    }

}

scaramouche's solution fails when there is a single instance used for all JobExecutions( returning the singleton using a custom JobFactory class, rather than calling newInstance() for each execution)