PunctuationSchedule is a
Stamped of ProcessorNodes.
PunctuationSchedule takes the following to be created:
PunctuationSchedule is created when:
PunctuationScheduleis requested for the next PunctuationSchedule
StreamTaskis requested to schedule a punctuator
isCancelled internal flag when created.
isCancelled is off (
false) by default and can be turned on (
true) in markCancelled.
markCancelled turns the isCancelled flag on.