org.apache.flink.streaming.api.windowing.triggers

Class ProcessingTimeTrigger

java.lang.Object

org.apache.flink.streaming.api.windowing.triggers.Trigger<Object,TimeWindow>

org.apache.flink.streaming.api.windowing.triggers.ProcessingTimeTrigger

All Implemented Interfaces:

Serializable

@PublicEvolving
public class ProcessingTimeTrigger
extends Trigger<Object,TimeWindow>

A Trigger that fires once the current system time passes the end of the window to which a pane belongs.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.flink.streaming.api.windowing.triggers.Trigger

Trigger.TriggerContext

Method Summary

Modifier and Type	Method and Description
void	clear(TimeWindow window, Trigger.TriggerContext ctx) Clears any state that the trigger might still hold for the given window.
static ProcessingTimeTrigger	create() Creates a new trigger that fires once system time passes the end of the window.
TriggerResult	onElement(Object element, long timestamp, TimeWindow window, Trigger.TriggerContext ctx) Called for every element that gets added to a pane.
TriggerResult	onEventTime(long time, TimeWindow window, Trigger.TriggerContext ctx) Called when an event-time timer that was set using the trigger context fires.
TriggerResult	onProcessingTime(long time, TimeWindow window, Trigger.TriggerContext ctx) Called when a processing-time timer that was set using the trigger context fires.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

onElement

public TriggerResult onElement(Object element,
                               long timestamp,
                               TimeWindow window,
                               Trigger.TriggerContext ctx)

Description copied from class: Trigger

Called for every element that gets added to a pane. The result of this will determine whether the pane is evaluated to emit results.

Specified by:

onElement in class Trigger<Object,TimeWindow>

Parameters:

element - The element that arrived.

timestamp - The timestamp of the element that arrived.

window - The window to which this pane belongs.

ctx - A context object that can be used to register timer callbacks.

onEventTime

public TriggerResult onEventTime(long time,
                                 TimeWindow window,
                                 Trigger.TriggerContext ctx)
                          throws Exception

Description copied from class: Trigger

Called when an event-time timer that was set using the trigger context fires.

Specified by:

onEventTime in class Trigger<Object,TimeWindow>

Parameters:

time - The timestamp at which the timer fired.

ctx - A context object that can be used to register timer callbacks.

Throws:

Exception

onProcessingTime

public TriggerResult onProcessingTime(long time,
                                      TimeWindow window,
                                      Trigger.TriggerContext ctx)

Description copied from class: Trigger

Called when a processing-time timer that was set using the trigger context fires.

Specified by:

onProcessingTime in class Trigger<Object,TimeWindow>

Parameters:

time - The timestamp at which the timer fired.

ctx - A context object that can be used to register timer callbacks.

clear

public void clear(TimeWindow window,
                  Trigger.TriggerContext ctx)
           throws Exception

Description copied from class: Trigger

Clears any state that the trigger might still hold for the given window. This is called when a window is purged. Timers set using Trigger.TriggerContext.registerEventTimeTimer(long) and Trigger.TriggerContext.registerProcessingTimeTimer(long) should be deleted here as well as state acquired using Trigger.TriggerContext.getPartitionedState(StateDescriptor).

By default, this method does nothing.

Overrides:

clear in class Trigger<Object,TimeWindow>

Throws:

Exception

toString

public String toString()

Overrides:

toString in class Object

create

public static ProcessingTimeTrigger create()

Creates a new trigger that fires once system time passes the end of the window.