code: public Workflow getWorkflow(String workflowId, boolean includeTasks) {
          Preconditions.checkArgument(StringUtils.isNotBlank(workflowId), "workflow id cannot be blank");
          Workflow workflow = getForEntity("workflow/{workflowId}", new Object[]{"includeTasks", includeTasks}, Workflow.class, workflowId);
          populateWorkflowOutput(workflow);
          return workflow;
      }
docs: Retrieve a workflow by workflow id
  
  @param workflowId   the id of the workflow
  @param includeTasks specify if the tasks in the workflow need to be returned
  @return the requested workflow