public class JobInstance
Batch domain object representing a uniquely identifiable job run.
JobInstance can be restarted multiple times in case of execution failure and
it's lifecycle ends with first successful execution.
Trying to execute an existing JobIntance that has already completed
successfully will result in error. Error will be raised also for an attempt
to restart a failed JobInstance if the Job is not restartable.
Lucas Ward, Dave Syer, Robert Kasanicky, Michael Minella