我正在想办法写我自己的 WindowFunction 但是有问题，我不知道为什么。我遇到的问题是apply函数，因为它无法识别 MyWindowFunction 作为一个有效的输入，所以我不能编译。我正在传输的数据包含 (timestamp,x,y) 其中x和y分别为0和1。 extractTupleWithoutTs 只返回一个元组 (x,y) . 我已经用简单的求和函数和reduce函数成功地运行了代码。感谢您的帮助：）使用flink 1.3
进口：

import org.apache.flink.streaming.api.TimeCharacteristic
import org.apache.flink.streaming.api.functions.AssignerWithPeriodicWatermarks
import org.apache.flink.streaming.api.scala.function.WindowFunction
import org.apache.flink.streaming.api.watermark.Watermark
import org.apache.flink.streaming.api.windowing.windows.TimeWindow
import org.apache.flink.util.Collector

其余代码：

val env = StreamExecutionEnvironment.getExecutionEnvironment
env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime)
val text = env.socketTextStream("localhost", 9999).assignTimestampsAndWatermarks(new TsExtractor)
val tuple = text.map( str => extractTupleWithoutTs(str))
val counts = tuple.keyBy(0).timeWindow(Time.seconds(5)).apply(new MyWindowFunction())
counts.print()
env.execute("Window Stream")

mywindow函数，它基本上是复制粘贴从示例中修改的类型。

class MyWindowFunction extends WindowFunction[(Int, Int), Int, Int, TimeWindow] {
  def apply(key: Int, window: TimeWindow, input: Iterable[(Int, Int)], out: Collector[Int]): () = {
    var count = 0
    for (in <- input) {
      count = count + 1
    }
    out.collect(count)
  }
}