flink-streaming - 窗口的开始和结束时间

Question

显示窗口开始和结束时间的方法是什么？诸如实现用户定义的窗口之类的东西？

想知道窗口开始和评估的时间，以便输出为

quantity(WindowAll Sum), window_start_time, window_end_time
12, 1:13:21, 1:13:41
6, 1:13:41, 1:15:01

Answer 1

找到了答案。TimeWindow.class有 getStart() 和 getEnd()

示例用法：

public static class SumAllWindow implements AllWindowFunction<Tuple2<String,Integer>,
        Tuple3<Integer, String, String>, TimeWindow> {

    private static transient DateTimeFormatter timeFormatter =
            DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss.SS").withLocale(Locale.GERMAN).
                    withZone(DateTimeZone.forID("Europe/Berlin"));

    @Override
    public void apply (TimeWindow window, Iterable<Tuple2<String, Integer>> values,
                       Collector<Tuple3<Integer, String, String>> out) throws Exception {

        DateTime startTs = new DateTime(window.getStart(), DateTimeZone.forID("Europe/Berlin"));
        DateTime endTs = new DateTime(window.getEnd(), DateTimeZone.forID("Europe/Berlin"));

        int sum = 0;
        for (Tuple2<String, Integer> value : values) {
            sum += value.f1;
        }
        out.collect(new Tuple3<>(sum, startTs.toString(timeFormatter), endTs.toString(timeFormatter)));
    }
}

在主（）

msgStream.timeWindowAll(Time.of(6, TimeUnit.SECONDS)).apply(new SumAllWindow()).print();