org.apache.kafka.streams.kstream

Class Windows<W extends Window>

java.lang.Object

org.apache.kafka.streams.kstream.Windows<W>

Type Parameters:

W - type of the window instance

Direct Known Subclasses:

JoinWindows, TimeWindows, UnlimitedWindows

public abstract class Windows<W extends Window>
extends Object

The window specification interface that can be extended for windowing operation in joins and aggregations.

Field Summary

Fields

Modifier and Type	Field and Description
int	segments

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Windows()

Method Summary

Methods

Modifier and Type	Method and Description
long	maintainMs() Return the window maintain duration in milliseconds of system time.
protected Windows<W>	segments(int segments) Specify the number of segments to be used for rolling the window store, this function is not exposed to users but can be called by developers that extend this JoinWindows specs.
abstract long	size()
Windows<W>	until(long durationMs) Set the window maintain duration in milliseconds of streams time.
abstract Map<Long,W>	windowsFor(long timestamp) Creates all windows that contain the provided timestamp, indexed by non-negative window start timestamps.

Methods inherited from class java.lang.Object

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

Field Detail

segments

public int segments

Constructor Detail

Windows

protected Windows()

Method Detail

until

public Windows<W> until(long durationMs)

Set the window maintain duration in milliseconds of streams time. This retention time is a guaranteed lower bound for how long a window will be maintained.

Returns:

itself

segments

protected Windows<W> segments(int segments)

Specify the number of segments to be used for rolling the window store, this function is not exposed to users but can be called by developers that extend this JoinWindows specs.

Returns:

itself

maintainMs

public long maintainMs()

Return the window maintain duration in milliseconds of system time.

Returns:

the window maintain duration in milliseconds of system time

windowsFor

public abstract Map<Long,W> windowsFor(long timestamp)

Creates all windows that contain the provided timestamp, indexed by non-negative window start timestamps.

Parameters:

timestamp - the timestamp window should get created for

Returns:

a map of windowStartTimestamp -> Window entries

size

public abstract long size()