Package org.apache.flink.runtime.asyncprocessing.operators.windowing.triggers

Class AsyncEventTimeTrigger

java.lang.Object

org.apache.flink.runtime.asyncprocessing.operators.windowing.triggers.AsyncTrigger<Object,TimeWindow>

org.apache.flink.runtime.asyncprocessing.operators.windowing.triggers.AsyncEventTimeTrigger

All Implemented Interfaces:

Serializable

@Experimental
public class AsyncEventTimeTrigger
extends AsyncTrigger<Object,TimeWindow>

A AsyncTrigger that fires once the watermark passes the end of the window to which a pane belongs. This is for async window operator.

See Also:

• Watermark
• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.flink.runtime.asyncprocessing.operators.windowing.triggers.AsyncTrigger

AsyncTrigger.OnMergeContext, AsyncTrigger.TriggerContext

Method Summary

Modifier and Type	Method	Description
boolean	canMerge()	Returns true if this trigger supports merging of trigger state and can therefore be used with a MergingWindowAssigner.
org.apache.flink.api.common.state.v2.StateFuture<Void>	clear(TimeWindow window, AsyncTrigger.TriggerContext ctx)	Clears any state that the trigger might still hold for the given window.
static AsyncEventTimeTrigger	create()	Creates an event-time trigger that fires once the watermark passes the end of the window.
org.apache.flink.api.common.state.v2.StateFuture<TriggerResult>	onElement(Object element, long timestamp, TimeWindow window, AsyncTrigger.TriggerContext ctx)	Called for every element that gets added to a pane.
org.apache.flink.api.common.state.v2.StateFuture<TriggerResult>	onEventTime(long time, TimeWindow window, AsyncTrigger.TriggerContext ctx)	Called when an event-time timer that was set using the trigger context fires.
void	onMerge(TimeWindow window, AsyncTrigger.OnMergeContext ctx)	Called when several windows have been merged into one window by the WindowAssigner.
org.apache.flink.api.common.state.v2.StateFuture<TriggerResult>	onProcessingTime(long time, TimeWindow window, AsyncTrigger.TriggerContext ctx)	Called when a processing-time timer that was set using the trigger context fires.
String	toString()

Methods inherited from class org.apache.flink.runtime.asyncprocessing.operators.windowing.triggers.AsyncTrigger

isEndOfStreamTrigger

Methods inherited from class java.lang.Object

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

Method Details

onElement

public org.apache.flink.api.common.state.v2.StateFuture<TriggerResult> onElement(Object element,
 long timestamp,
 TimeWindow window,
 AsyncTrigger.TriggerContext ctx)
                                                                          throws Exception

Description copied from class: AsyncTrigger

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 AsyncTrigger<Object,TimeWindow>

Parameters:

element - The element that arrived.

timestamp - The timestamp of the element that arrived.

window - The window to which the element is being added.

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

Throws:

Exception

onEventTime

public org.apache.flink.api.common.state.v2.StateFuture<TriggerResult> onEventTime(long time,
 TimeWindow window,
 AsyncTrigger.TriggerContext ctx)

Description copied from class: AsyncTrigger

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

Specified by:

onEventTime in class AsyncTrigger<Object,TimeWindow>

Parameters:

time - The timestamp at which the timer fired.

window - The window for which the timer fired.

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

onProcessingTime

public org.apache.flink.api.common.state.v2.StateFuture<TriggerResult> onProcessingTime(long time,
 TimeWindow window,
 AsyncTrigger.TriggerContext ctx)
                                                                                 throws Exception

Description copied from class: AsyncTrigger

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

Specified by:

onProcessingTime in class AsyncTrigger<Object,TimeWindow>

Parameters:

time - The timestamp at which the timer fired.

window - The window for which the timer fired.

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

Throws:

Exception

clear

public org.apache.flink.api.common.state.v2.StateFuture<Void> clear(TimeWindow window,
 AsyncTrigger.TriggerContext ctx)
                                                             throws Exception

Description copied from class: AsyncTrigger

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

Specified by:

clear in class AsyncTrigger<Object,TimeWindow>

Throws:

Exception

canMerge

public boolean canMerge()

Description copied from class: AsyncTrigger

Returns true if this trigger supports merging of trigger state and can therefore be used with a MergingWindowAssigner.

If this returns true you must properly implement AsyncTrigger.onMerge(Window, OnMergeContext)

Overrides:

canMerge in class AsyncTrigger<Object,TimeWindow>

onMerge

public void onMerge(TimeWindow window,
 AsyncTrigger.OnMergeContext ctx)

Description copied from class: AsyncTrigger

Called when several windows have been merged into one window by the WindowAssigner.

Overrides:

onMerge in class AsyncTrigger<Object,TimeWindow>

Parameters:

window - The new window that results from the merge.

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

toString

public String toString()

Overrides:

toString in class Object

create

public static AsyncEventTimeTrigger create()

Creates an event-time trigger that fires once the watermark passes the end of the window.

Once the trigger fires all elements are discarded. Elements that arrive late immediately trigger window evaluation with just this one element.