Class AlignedWatermarkCombiner

java.lang.Object
org.apache.flink.streaming.runtime.watermark.AlignedWatermarkCombiner
All Implemented Interfaces:
WatermarkCombiner

public class AlignedWatermarkCombiner extends Object implements WatermarkCombiner
A WatermarkCombiner is design to align Watermarks. It will combine watermarks after receiving watermarks from all upstream input channels.

The combine process will perform the following three steps: (1) send the combined watermark (actually the last received watermark) to downstream, (2) clear the received watermarks, (3) resume input gate.

Note that the aligned Watermarks should have the same value within a batch.

  • Constructor Details

    • AlignedWatermarkCombiner

      public AlignedWatermarkCombiner(int numberOfInputChannels, Runnable gateResumer)
  • Method Details

    • combineWatermark

      public void combineWatermark(org.apache.flink.api.common.watermark.Watermark watermark, int channelIndex, Consumer<org.apache.flink.api.common.watermark.Watermark> watermarkEmitter) throws Exception
      Specified by:
      combineWatermark in interface WatermarkCombiner
      Throws:
      Exception