code: public void stop() throws Exception {
  		LOG.info("Stop job leader service.");
  
  		if (JobLeaderService.State.STARTED == state) {
  
  			for (Tuple2<LeaderRetrievalService, JobLeaderService.JobManagerLeaderListener> leaderRetrievalServiceEntry: jobLeaderServices.values()) {
  				LeaderRetrievalService leaderRetrievalService = leaderRetrievalServiceEntry.f0;
  				JobLeaderService.JobManagerLeaderListener jobManagerLeaderListener = leaderRetrievalServiceEntry.f1;
  
  				jobManagerLeaderListener.stop();
  				leaderRetrievalService.stop();
  			}
  
  			jobLeaderServices.clear();
  		}
  
  		state = JobLeaderService.State.STOPPED;
  	}
docs: Stop the job leader services. This implies stopping all leader retrieval services for the
  different jobs and their leader retrieval listeners.
  
  @throws Exception if an error occurs while stopping the service