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

Class DeltaTrigger<T,W extends org.apache.flink.streaming.api.windowing.windows.Window>

java.lang.Object

org.apache.flink.streaming.api.windowing.triggers.Trigger<T,W>

org.apache.flink.streaming.api.windowing.triggers.DeltaTrigger<T,W>

Type Parameters:

W - The type of Windows on which this trigger can operate.

All Implemented Interfaces:

Serializable

@PublicEvolving
public class DeltaTrigger<T,W extends org.apache.flink.streaming.api.windowing.windows.Window>
extends org.apache.flink.streaming.api.windowing.triggers.Trigger<T,W>

A Trigger that fires based on a DeltaFunction and a threshold.

This trigger calculates a delta between the data point which triggered last and the currently arrived data point. It triggers if the delta is higher than a specified threshold.

See Also:

Serialized Form

Nested Class Summary

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

org.apache.flink.streaming.api.windowing.triggers.Trigger.OnMergeContext, org.apache.flink.streaming.api.windowing.triggers.Trigger.TriggerContext

Method Summary

Modifier and Type	Method	Description
void	clear(W window, org.apache.flink.streaming.api.windowing.triggers.Trigger.TriggerContext ctx)
static <T,W extends org.apache.flink.streaming.api.windowing.windows.Window> DeltaTrigger<T,W>	of(double threshold, DeltaFunction<T> deltaFunction, org.apache.flink.api.common.typeutils.TypeSerializer<T> stateSerializer)	Creates a delta trigger from the given threshold and DeltaFunction.
org.apache.flink.streaming.api.windowing.triggers.TriggerResult	onElement(T element, long timestamp, W window, org.apache.flink.streaming.api.windowing.triggers.Trigger.TriggerContext ctx)
org.apache.flink.streaming.api.windowing.triggers.TriggerResult	onEventTime(long time, W window, org.apache.flink.streaming.api.windowing.triggers.Trigger.TriggerContext ctx)
org.apache.flink.streaming.api.windowing.triggers.TriggerResult	onProcessingTime(long time, W window, org.apache.flink.streaming.api.windowing.triggers.Trigger.TriggerContext ctx)
String	toString()

Methods inherited from class org.apache.flink.streaming.api.windowing.triggers.Trigger

canMerge, onMerge

Methods inherited from class java.lang.Object

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

Method Detail

onElement

public org.apache.flink.streaming.api.windowing.triggers.TriggerResult onElement(T element,
                                                                                 long timestamp,
                                                                                 W window,
                                                                                 org.apache.flink.streaming.api.windowing.triggers.Trigger.TriggerContext ctx)
                                                                          throws Exception

Specified by:

onElement in class org.apache.flink.streaming.api.windowing.triggers.Trigger<T,W extends org.apache.flink.streaming.api.windowing.windows.Window>

Throws:

Exception

onEventTime

public org.apache.flink.streaming.api.windowing.triggers.TriggerResult onEventTime(long time,
                                                                                   W window,
                                                                                   org.apache.flink.streaming.api.windowing.triggers.Trigger.TriggerContext ctx)

Specified by:

onEventTime in class org.apache.flink.streaming.api.windowing.triggers.Trigger<T,W extends org.apache.flink.streaming.api.windowing.windows.Window>

onProcessingTime

public org.apache.flink.streaming.api.windowing.triggers.TriggerResult onProcessingTime(long time,
                                                                                        W window,
                                                                                        org.apache.flink.streaming.api.windowing.triggers.Trigger.TriggerContext ctx)
                                                                                 throws Exception

Specified by:

onProcessingTime in class org.apache.flink.streaming.api.windowing.triggers.Trigger<T,W extends org.apache.flink.streaming.api.windowing.windows.Window>

Throws:

Exception

clear

public void clear(W window,
                  org.apache.flink.streaming.api.windowing.triggers.Trigger.TriggerContext ctx)
           throws Exception

Specified by:

clear in class org.apache.flink.streaming.api.windowing.triggers.Trigger<T,W extends org.apache.flink.streaming.api.windowing.windows.Window>

Throws:

Exception

toString

public String toString()

Overrides:

toString in class Object

of

public static <T,W extends org.apache.flink.streaming.api.windowing.windows.Window> DeltaTrigger<T,W> of(double threshold,
                                                                                                                     DeltaFunction<T> deltaFunction,
                                                                                                                     org.apache.flink.api.common.typeutils.TypeSerializer<T> stateSerializer)

Creates a delta trigger from the given threshold and DeltaFunction.

Type Parameters:

T - The type of elements on which this trigger can operate.

W - The type of Windows on which this trigger can operate.

Parameters:

threshold - The threshold at which to trigger.

deltaFunction - The delta function to use

stateSerializer - TypeSerializer for the data elements.