code: @Override
      public CancelJobResult cancelJob(CancelJobRequest request) {
          request = beforeClientExecution(request);
          return executeCancelJob(request);
      }
docs: <p>
  Cancels a job in an AWS Batch job queue. Jobs that are in the <code>SUBMITTED</code>, <code>PENDING</code>, or
  <code>RUNNABLE</code> state are cancelled. Jobs that have progressed to <code>STARTING</code> or
  <code>RUNNING</code> are not cancelled (but the API operation still succeeds, even if no job is cancelled); these
  jobs must be terminated with the <a>TerminateJob</a> operation.
  </p>
  
  @param cancelJobRequest
  @return Result of the CancelJob operation returned by the service.
  @throws ClientException
  These errors are usually caused by a client action, such as using an action or resource on behalf of a
  user that doesn't have permissions to use the action or resource, or specifying an identifier that is not
  valid.
  @throws ServerException
  These errors are usually caused by a server issue.
  @sample AWSBatch.CancelJob
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/batch-2016-08-10/CancelJob" target="_top">AWS API
  Documentation</a>