private[spark] trait JobListener {
def taskSucceeded(index: Int, result: Any)
def jobFailed(exception: Exception)
}
JobListener
Spark subscribes for job completion or failure events (after submitting a job to DAGScheduler) using JobListener trait.
The following are the job listeners used:
-
JobWaiter waits until DAGScheduler completes a job and passes the results of tasks to a
resultHandlerfunction. -
ApproximateActionListener…FIXME
An instance of JobListener is used in the following places:
-
In
ActiveJobas a listener to notify if tasks in this job finish or the job fails. -
In
JobSubmitted
JobListener Contract
JobListener is a private[spark] contract with the following two methods:
A JobListener object is notified each time a task succeeds (by taskSucceeded) and when the whole job fails (by jobFailed).