Package org.apache.flink.datastream.api.extension.window.function

Interface WindowProcessFunction

All Superinterfaces:
org.apache.flink.api.common.functions.Function, ProcessFunction, Serializable
All Known Subinterfaces:
OneInputWindowStreamProcessFunction<IN,OUT>, TwoInputNonBroadcastWindowStreamProcessFunction<IN1,IN2,OUT>, TwoOutputWindowStreamProcessFunction<IN,OUT1,OUT2>
@Experimental public interface WindowProcessFunction extends ProcessFunction
Base interface for functions evaluated over windows, providing callback functions for various stages of the window's lifecycle.

  • Method Summary

    Modifier and Type
    Method
    Description
    default Set<org.apache.flink.api.common.state.StateDeclaration>
    useWindowStates()
    Explicitly declares states that are bound to the window.

    Methods inherited from interface org.apache.flink.datastream.api.function.ProcessFunction

    close, declareWatermarks, usesStates

  • Method Details

    • useWindowStates

      default Set<org.apache.flink.api.common.state.StateDeclaration> useWindowStates()
      Explicitly declares states that are bound to the window. Each specific window state must be declared in this method before it can be used.
      Returns:
      all declared window states used by this process function.