Count Window

package com.atguigu.window;

import com.atguigu.bean.WaterSensor;
import com.atguigu.functions.WaterSensorMapFunction;
import org.apache.commons.lang3.time.DateFormatUtils;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.datastream.WindowedStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.windowing.ProcessWindowFunction;
import org.apache.flink.streaming.api.windowing.windows.GlobalWindow;
import org.apache.flink.util.Collector;

public class CountWindowDemo {
    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        env.setParallelism(1);

        SingleOutputStreamOperator<WaterSensor> sensorDS = env
                .socketTextStream("192.168.1.7", 9091)
                .map(new WaterSensorMapFunction());

        KeyedStream<WaterSensor, String> sensorKS = sensorDS.keyBy(sensor -> sensor.getId());

        // 1. 窗口分配器
        WindowedStream<WaterSensor, String, GlobalWindow> sensorWS = sensorKS
//                .countWindow(5); // 滚动窗口，窗口长度5条数据
                .countWindow(5, 2); //滑动窗口，窗口长度5条数据，滑动步长2条数据（每经过一个步长，都有一个窗口触发输出，第一次输出在第2条数据来的时候）

        SingleOutputStreamOperator<String> process = sensorWS
                .process(
                        new ProcessWindowFunction<WaterSensor, String, String, GlobalWindow>() {
                            @Override
                            public void process(String s, Context context, Iterable<WaterSensor> elements, Collector<String> out) throws Exception {
                                long maxTs = context.window().maxTimestamp();
                                String maxTime = DateFormatUtils.format(maxTs, "yyyy-MM-dd HH:mm:ss.SSS");
                                long count = elements.spliterator().estimateSize();

                                out.collect("key=" + s + "的窗口最大时间=" + maxTime + ",包含" + count + "条数据===>" + elements.toString());
                            }
                        }
                );

        process.print();

        env.execute();
    }
}