Class WaterMarkEventGenerator<T>

All Implemented Interfaces:

public class WaterMarkEventGenerator<T> extends Object implements Runnable
Tracks tuples across input streams and periodically emits watermark events. Watermark event timestamp is the minimum of the latest tuple timestamps across all the input streams (minus the lag). Once a watermark event is emitted any tuple coming with an earlier timestamp can be considered as late events.
  • Constructor Details

    • WaterMarkEventGenerator

      public WaterMarkEventGenerator(WindowManager<T> windowManager, int intervalMs, int eventTsLagMs, Set<GlobalStreamId> inputStreams)
      Creates a new WatermarkEventGenerator.
      windowManager - The window manager this generator will submit watermark events to
      intervalMs - The generator will check if it should generate a watermark event with this interval
      eventTsLagMs - The max allowed lag behind the last watermark event before an event is considered late
      inputStreams - The input streams this generator is expected to handle
  • Method Details

    • track

      public boolean track(GlobalStreamId stream, long ts)
      Tracks the timestamp of the event in the stream, returns true if the event can be considered for processing or false if its a late event.
    • run

      public void run()
      Specified by:
      run in interface Runnable
    • start

      public void start()
    • shutdown

      public void shutdown()