Class ReduceApplyWindowFunction<K,​W extends Window,​T,​R>

  • All Implemented Interfaces:
    Serializable, org.apache.flink.api.common.functions.Function, org.apache.flink.api.common.functions.RichFunction, WindowFunction<T,​R,​K,​W>

    @Internal
    public class ReduceApplyWindowFunction<K,​W extends Window,​T,​R>
    extends org.apache.flink.api.common.functions.WrappingFunction<WindowFunction<T,​R,​K,​W>>
    implements WindowFunction<T,​R,​K,​W>
    Internal WindowFunction that is used for implementing a fold on a window configuration that only allows WindowFunction and cannot directly execute a ReduceFunction.
    See Also:
    Serialized Form
    • Field Summary

      • Fields inherited from class org.apache.flink.api.common.functions.WrappingFunction

        wrappedFunction
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void apply​(K k, W window, Iterable<T> input, org.apache.flink.util.Collector<R> out)
      Evaluates the window and outputs none or several elements.
      • Methods inherited from class org.apache.flink.api.common.functions.WrappingFunction

        close, getWrappedFunction, open, setRuntimeContext
      • Methods inherited from class org.apache.flink.api.common.functions.AbstractRichFunction

        getIterationRuntimeContext, getRuntimeContext
    • Constructor Detail

      • ReduceApplyWindowFunction

        public ReduceApplyWindowFunction​(org.apache.flink.api.common.functions.ReduceFunction<T> reduceFunction,
                                         WindowFunction<T,​R,​K,​W> windowFunction)
    • Method Detail

      • apply

        public void apply​(K k,
                          W window,
                          Iterable<T> input,
                          org.apache.flink.util.Collector<R> out)
                   throws Exception
        Description copied from interface: WindowFunction
        Evaluates the window and outputs none or several elements.
        Specified by:
        apply in interface WindowFunction<K,​W extends Window,​T,​R>
        Parameters:
        k - The key for which this window is evaluated.
        window - The window that is being evaluated.
        input - The elements in the window being evaluated.
        out - A collector for emitting elements.
        Throws:
        Exception - The function may throw exceptions to fail the program and trigger recovery.