code: @Override
    public void onFileChange(Path path) {
      String fileExtension = path.getName().substring(path.getName().lastIndexOf('.') + 1);
      if (fileExtension.equalsIgnoreCase(SchedulerUtils.JOB_PROPS_FILE_EXTENSION)) {
        LOG.info("Detected change to common properties file " + path.toString());
        loadNewCommonConfigAndHandleNewJob(path, JobScheduler.Action.RESCHEDULE);
        return;
      }
  
      if (!jobScheduler.jobConfigFileExtensions.contains(fileExtension)) {
        // Not a job configuration file, ignore.
        return;
      }
  
      LOG.info("Detected change to job configuration file " + path.toString());
      loadNewJobConfigAndHandleNewJob(path, JobScheduler.Action.RESCHEDULE);
    }
docs: Called when a job configuration file is changed.