org.apache.beam.sdk.transforms.splittabledofn

Interface ManualWatermarkEstimator<WatermarkEstimatorStateT>

All Superinterfaces:

WatermarkEstimator<WatermarkEstimatorStateT>

All Known Implementing Classes:

WatermarkEstimators.Manual

@Experimental(value=SPLITTABLE_DO_FN)
public interface ManualWatermarkEstimator<WatermarkEstimatorStateT>
extends WatermarkEstimator<WatermarkEstimatorStateT>

A WatermarkEstimator which is controlled manually from within a DoFn. The DoFn must invoke setWatermark(org.joda.time.Instant) to advance the watermark. See WatermarkEstimators.Manual for a concrete implementation.

Method Summary

Modifier and Type	Method and Description
void	setWatermark(Instant watermark) Sets a timestamp before or at the timestamps of all future elements produced by the associated DoFn.

Methods inherited from interface org.apache.beam.sdk.transforms.splittabledofn.WatermarkEstimator

currentWatermark, getState

Method Detail

setWatermark

void setWatermark(Instant watermark)

Sets a timestamp before or at the timestamps of all future elements produced by the associated DoFn.

This can be approximate. If records are output that violate this guarantee, they will be considered late, which will affect how they will be processed. See watermarks and late data for more information on late data and how to handle it.

However, this value should be as late as possible. Downstream windows may not be able to close until this watermark passes their end.