code: @Override
  	public int getCurrentlyExecutingAmount(JobKey jobKey) throws SchedulerException {
  		List<JobExecutionContext> executingJobs = scheduler.getCurrentlyExecutingJobs();
  		JobDetail jobDetail = scheduler.getJobDetail(jobKey);
  		int numInstances = 0;
  		for (JobExecutionContext jobExecutionContext : executingJobs) {
  			JobDetail execJobDetail = jobExecutionContext.getJobDetail();
  			if (execJobDetail.getKey().equals(jobDetail.getKey())) {
  				if (LOGGER.isTraceEnabled()) 
  					LOGGER.trace(String.format("found running job for jobkey: (%s, %s)", jobKey.getGroup(), jobKey.getName()));
  				++numInstances;
  			}
  		}
  		return numInstances;
  	}
docs: /* (non-Javadoc)
  @see de.chandre.admintool.quartz.AdminToolQuartzService#getCurrentlyExecutingAmount(org.quartz.JobKey)