org.apache.flink.table.runtime.operators.window.tvf.common

Interface WindowAssigner

All Superinterfaces:

Serializable

All Known Subinterfaces:

SliceAssigner, SliceSharedAssigner, SliceUnsharedAssigner, UnsliceAssigner<W>

All Known Implementing Classes:

SliceAssigners.CumulativeSliceAssigner, SliceAssigners.HoppingSliceAssigner, SliceAssigners.SlicedSharedSliceAssigner, SliceAssigners.SlicedUnsharedSliceAssigner, SliceAssigners.TumblingSliceAssigner, SliceAssigners.WindowedSliceAssigner, UnsliceAssigners.SessionUnsliceAssigner, UnsliceAssigners.WindowedUnsliceAssigner

@Internal
public interface WindowAssigner
extends Serializable

WindowAssigner is used to assign windows to elements.

The differences between WindowAssigner and GroupWindowAssigner is that, this window assigner is translated from the new window TVF syntax, but the other is from the legacy GROUP WINDOW FUNCTION syntax. In the long future, GroupWindowAssigner will be dropped.

See more details in WindowAggOperator.

Method Summary

Modifier and Type	Method and Description
String	getDescription() Returns a description of this window assigner.
boolean	isEventTime() Returns true if elements are assigned to windows based on event time, false based on processing time.

Method Detail

isEventTime

boolean isEventTime()

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

getDescription

String getDescription()

Returns a description of this window assigner.