org.apache.flink.table.runtime.operators.window.assigners

Class SlidingWindowAssigner

java.lang.Object

org.apache.flink.table.runtime.operators.window.assigners.WindowAssigner<W>

org.apache.flink.table.runtime.operators.window.assigners.PanedWindowAssigner<TimeWindow>

org.apache.flink.table.runtime.operators.window.assigners.SlidingWindowAssigner

All Implemented Interfaces:

Serializable, InternalTimeWindowAssigner

public class SlidingWindowAssigner
extends PanedWindowAssigner<TimeWindow>
implements InternalTimeWindowAssigner

A WindowAssigner that windows elements into sliding windows based on the timestamp of the elements. Windows can possibly overlap.

See Also:

Serialized Form

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SlidingWindowAssigner(long size, long slide, long offset, boolean isEventTime)

Method Summary

Modifier and Type	Method and Description
TimeWindow	assignPane(Object element, long timestamp) Given the timestamp and element, returns the pane into which it should be placed.
Collection<TimeWindow>	assignWindows(org.apache.flink.table.data.RowData element, long timestamp) Given the timestamp and element, returns the set of windows into which it should be placed.
TimeWindow	getLastWindow(TimeWindow pane) Gets the last window which the pane belongs to.
org.apache.flink.api.common.typeutils.TypeSerializer<TimeWindow>	getWindowSerializer(org.apache.flink.api.common.ExecutionConfig executionConfig) Returns a TypeSerializer for serializing windows that are assigned by this WindowAssigner.
boolean	isEventTime() Returns true if elements are assigned to windows based on event time, false otherwise.
static SlidingWindowAssigner	of(java.time.Duration size, java.time.Duration slide) Creates a new SlidingEventTimeWindows WindowAssigner that assigns elements to sliding time windows based on the element timestamp.
Iterable<TimeWindow>	splitIntoPanes(TimeWindow window) Splits the given window into panes collection.
String	toString()
SlidingWindowAssigner	withEventTime()
SlidingWindowAssigner	withOffset(java.time.Duration offset)
SlidingWindowAssigner	withProcessingTime()

Methods inherited from class org.apache.flink.table.runtime.operators.window.assigners.WindowAssigner

open

Methods inherited from class java.lang.Object

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

Constructor Detail

SlidingWindowAssigner

protected SlidingWindowAssigner(long size,
                                long slide,
                                long offset,
                                boolean isEventTime)

Method Detail

assignWindows

public Collection<TimeWindow> assignWindows(org.apache.flink.table.data.RowData element,
                                            long timestamp)

Description copied from class: WindowAssigner

Given the timestamp and element, returns the set of windows into which it should be placed.

Specified by:

assignWindows in class WindowAssigner<TimeWindow>

Parameters:

element - The element to which windows should be assigned.

timestamp - The timestamp of the element when WindowAssigner.isEventTime() returns true, or the current system time when WindowAssigner.isEventTime() returns false. The timestamp value is mapping to UTC milliseconds for splitting windows simply.

assignPane

public TimeWindow assignPane(Object element,
                             long timestamp)

Description copied from class: PanedWindowAssigner

Given the timestamp and element, returns the pane into which it should be placed.

Specified by:

assignPane in class PanedWindowAssigner<TimeWindow>

Parameters:

element - The element to which windows should be assigned.

timestamp - The timestamp of the element when WindowAssigner.isEventTime() returns true, or the current system time when WindowAssigner.isEventTime() returns false.

splitIntoPanes

public Iterable<TimeWindow> splitIntoPanes(TimeWindow window)

Description copied from class: PanedWindowAssigner

Splits the given window into panes collection.

Specified by:

splitIntoPanes in class PanedWindowAssigner<TimeWindow>

Parameters:

window - the window to be split.

Returns:

the panes iterable

getLastWindow

public TimeWindow getLastWindow(TimeWindow pane)

Description copied from class: PanedWindowAssigner

Gets the last window which the pane belongs to.

Specified by:

getLastWindow in class PanedWindowAssigner<TimeWindow>

getWindowSerializer

public org.apache.flink.api.common.typeutils.TypeSerializer<TimeWindow> getWindowSerializer(org.apache.flink.api.common.ExecutionConfig executionConfig)

Description copied from class: WindowAssigner

Returns a TypeSerializer for serializing windows that are assigned by this WindowAssigner.

Specified by:

getWindowSerializer in class WindowAssigner<TimeWindow>

isEventTime

public boolean isEventTime()

Description copied from class: WindowAssigner

Returns true if elements are assigned to windows based on event time, false otherwise.

Specified by:

isEventTime in class WindowAssigner<TimeWindow>

toString

public String toString()

Specified by:

toString in class WindowAssigner<TimeWindow>

of

public static SlidingWindowAssigner of(java.time.Duration size,
                                       java.time.Duration slide)

Creates a new SlidingEventTimeWindows WindowAssigner that assigns elements to sliding time windows based on the element timestamp.

Parameters:

size - The size of the generated windows.

slide - The slide interval of the generated windows.

Returns:

The time policy.

withOffset

public SlidingWindowAssigner withOffset(java.time.Duration offset)

withEventTime

public SlidingWindowAssigner withEventTime()

Specified by:

withEventTime in interface InternalTimeWindowAssigner

Returns:

an InternalTimeWindowAssigner which in event time mode.

withProcessingTime

public SlidingWindowAssigner withProcessingTime()

Specified by:

withProcessingTime in interface InternalTimeWindowAssigner

Returns:

an InternalTimeWindowAssigner which in processing time mode.