org.apache.flink.streaming.api.operators.source

Interface TimestampsAndWatermarks<T>

Type Parameters:

T - The type of the emitted records.

All Known Implementing Classes:

NoOpTimestampsAndWatermarks, ProgressiveTimestampsAndWatermarks

@Internal
public interface TimestampsAndWatermarks<T>

Basic interface for the timestamp extraction and watermark generation logic for the SourceReader.

Implementations of this class may or may not actually perform certain tasks, like watermark generation. For example, the batch-oriented implementation typically skips all watermark generation logic.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	TimestampsAndWatermarks.TimestampsAndWatermarksContextProvider
static interface	TimestampsAndWatermarks.WatermarkUpdateListener Lets the owner/creator of the output know about latest emitted watermark.

Method Summary

Modifier and Type	Method and Description
org.apache.flink.api.connector.source.ReaderOutput<T>	createMainOutput(PushingAsyncDataInput.DataOutput<T> output, TimestampsAndWatermarks.WatermarkUpdateListener watermarkCallback) Creates the ReaderOutput for the source reader, than internally runs the timestamp extraction and watermark generation.
static <E> TimestampsAndWatermarks<E>	createNoOpEventTimeLogic(org.apache.flink.api.common.eventtime.WatermarkStrategy<E> watermarkStrategy, org.apache.flink.metrics.MetricGroup metrics, org.apache.flink.util.clock.RelativeClock inputActivityClock)
static <E> TimestampsAndWatermarks<E>	createProgressiveEventTimeLogic(org.apache.flink.api.common.eventtime.WatermarkStrategy<E> watermarkStrategy, org.apache.flink.metrics.MetricGroup metrics, ProcessingTimeService timeService, long periodicWatermarkIntervalMillis, org.apache.flink.util.clock.RelativeClock mainInputActivityClock, org.apache.flink.util.clock.Clock clock, org.apache.flink.runtime.metrics.groups.TaskIOMetricGroup taskIOMetricGroup)
void	emitImmediateWatermark(long wallClockTimestamp) Emit a watermark immediately.
void	pauseOrResumeSplits(Collection<String> splitsToPause, Collection<String> splitsToResume)
void	startPeriodicWatermarkEmits() Starts emitting periodic watermarks, if this implementation produces watermarks, and if periodic watermarks are configured.
void	stopPeriodicWatermarkEmits() Stops emitting periodic watermarks.

Method Detail

createMainOutput

org.apache.flink.api.connector.source.ReaderOutput<T> createMainOutput(PushingAsyncDataInput.DataOutput<T> output,
                                                                       TimestampsAndWatermarks.WatermarkUpdateListener watermarkCallback)

Creates the ReaderOutput for the source reader, than internally runs the timestamp extraction and watermark generation.

startPeriodicWatermarkEmits

void startPeriodicWatermarkEmits()

Starts emitting periodic watermarks, if this implementation produces watermarks, and if periodic watermarks are configured.

Periodic watermarks are produced by periodically calling the WatermarkGenerator.onPeriodicEmit(WatermarkOutput) method of the underlying Watermark Generators.

stopPeriodicWatermarkEmits

void stopPeriodicWatermarkEmits()

Stops emitting periodic watermarks.

emitImmediateWatermark

void emitImmediateWatermark(long wallClockTimestamp)

Emit a watermark immediately.

pauseOrResumeSplits

void pauseOrResumeSplits(Collection<String> splitsToPause,
                         Collection<String> splitsToResume)

createProgressiveEventTimeLogic

static <E> TimestampsAndWatermarks<E> createProgressiveEventTimeLogic(org.apache.flink.api.common.eventtime.WatermarkStrategy<E> watermarkStrategy,
                                                                      org.apache.flink.metrics.MetricGroup metrics,
                                                                      ProcessingTimeService timeService,
                                                                      long periodicWatermarkIntervalMillis,
                                                                      org.apache.flink.util.clock.RelativeClock mainInputActivityClock,
                                                                      org.apache.flink.util.clock.Clock clock,
                                                                      org.apache.flink.runtime.metrics.groups.TaskIOMetricGroup taskIOMetricGroup)

createNoOpEventTimeLogic

static <E> TimestampsAndWatermarks<E> createNoOpEventTimeLogic(org.apache.flink.api.common.eventtime.WatermarkStrategy<E> watermarkStrategy,
                                                               org.apache.flink.metrics.MetricGroup metrics,
                                                               org.apache.flink.util.clock.RelativeClock inputActivityClock)