code: public boolean cancelJob(String slaveJobId) {
          final AnalysisResultFuture resultFuture = _runningJobs.remove(slaveJobId);
          if (resultFuture != null) {
              resultFuture.cancel();
              return true;
          }
          return false;
      }
docs: Cancels a slave job, referred by it's id.
  
  @param slaveJobId
  @return whether or not the job was (found and) cancelled.