org.apache.storm.windowing

Interface WindowLifecycleListener<T>

Type Parameters:

T - The type of Event in the window (e.g. Tuple).

public interface WindowLifecycleListener<T>

A callback for expiry, activation of events tracked by the WindowManager.

Method Summary

Modifier and Type	Method and Description
default void	onActivation(List<T> events, List<T> newEvents, List<T> expired, Long referenceTime) Called on activation of the window due to the TriggerPolicy.
default void	onActivation(Supplier<Iterator<T>> eventsIt, Supplier<Iterator<T>> newEventsIt, Supplier<Iterator<T>> expiredIt, Long referenceTime) Called on activation of the window due to the TriggerPolicy.
void	onExpiry(List<T> events) Called on expiry of events from the window due to EvictionPolicy.

Method Detail

onExpiry

void onExpiry(List<T> events)

Called on expiry of events from the window due to EvictionPolicy.

Parameters:

events - the expired events

onActivation

default void onActivation(List<T> events,
                          List<T> newEvents,
                          List<T> expired,
                          Long referenceTime)

Called on activation of the window due to the TriggerPolicy.

Parameters:

events - the list of current events in the window.

newEvents - the newly added events since last activation.

expired - the expired events since last activation.

referenceTime - the reference (event or processing) time that resulted in activation

onActivation

default void onActivation(Supplier<Iterator<T>> eventsIt,
                          Supplier<Iterator<T>> newEventsIt,
                          Supplier<Iterator<T>> expiredIt,
                          Long referenceTime)

Called on activation of the window due to the TriggerPolicy. This is typically invoked when the windows are persisted in state and is huge to be loaded entirely in memory.

Parameters:

eventsIt - a supplier of iterator over the list of current events in the window

newEventsIt - a supplier of iterator over the newly added events since the last ativation

expiredIt - a supplier of iterator over the expired events since the last activation

referenceTime - the reference (event or processing) time that resulted in activation