Validators are implemented for each workflow execution status Validators are applied in production code

private static final Map<WorkflowExecutionStatus, Validator> validators = new HashMap<WorkflowExecutionStatus, Validator>() {{
  put(WorkflowExecutionStatus.CREATED, new CreatedValidator());
  put(WorkflowExecutionStatus.RUNNING, new RunningValidator());
  put(WorkflowExecutionStatus.SUSPENDED, new SuspendedValidator());
  put(WorkflowExecutionStatus.COMPLETED, new CompletedValidator());
  put(WorkflowExecutionStatus.FAILED, new FailedValidator());
  put(WorkflowExecutionStatus.CANCELED, new CanceledValidator());
}};