石家庄网站建设就找企行家,怎样做有效的黄页网站,杭州网站的建设,网站没有流量怎么办一、双流JOIN
在Flink中, 支持两种方式的流的Join: Window Join和Interval Join
二、Window Join
窗口join会join具有相同的key并且处于同一个窗口中的两个流的元素. 注意: 1.所有的窗口join都是 inner join, 意味着a流中的元素如果在b流中没有对应的, 则a流中这个元素就不会…一、双流JOIN
在Flink中, 支持两种方式的流的Join: Window Join和Interval Join
二、Window Join
窗口join会join具有相同的key并且处于同一个窗口中的两个流的元素. 注意: 1.所有的窗口join都是 inner join, 意味着a流中的元素如果在b流中没有对应的, 则a流中这个元素就不会处理(就是忽略掉了) 2.join成功后的元素的会以所在窗口的最大时间作为其时间戳. 例如窗口[5,10), 则元素会以9作为自己的时间戳。 Window join 仍然可分为 滚动窗口、滑动窗口Join、会话窗口Join
滚动窗口Join代码段示例
package com.lyh.flink12;
import org.apache.flink.api.common.eventtime.SerializableTimestampAssigner;
import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.api.common.functions.JoinFunction;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.windowing.assigners.TumblingEventTimeWindows;
import org.apache.flink.streaming.api.windowing.time.Time;/*** Author lizhenchaoatguigu.cn* Date 2021/1/24 22:09*/
public class Flink01_Join_Window_Tumbling {public static void main(String[] args) {StreamExecutionEnvironment env StreamExecutionEnvironment.createLocalEnvironmentWithWebUI(new Configuration());env.setParallelism(1);SingleOutputStreamOperatorWaterSensor s1 env.socketTextStream(hadoop100, 8888) // 在socket终端只输入毫秒级别的时间戳.map(value - {String[] datas value.split(,);return new WaterSensor(datas[0], Long.valueOf(datas[1]), Integer.valueOf(datas[2]));}).assignTimestampsAndWatermarks(WatermarkStrategy.WaterSensorforMonotonousTimestamps().withTimestampAssigner(new SerializableTimestampAssignerWaterSensor() {Overridepublic long extractTimestamp(WaterSensor element, long recordTimestamp) {return element.getTs() * 1000;}}));SingleOutputStreamOperatorWaterSensor s2 env.socketTextStream(hadoop100, 9999) // 在socket终端只输入毫秒级别的时间戳.map(value - {String[] datas value.split(,);return new WaterSensor(datas[0], Long.valueOf(datas[1]), Integer.valueOf(datas[2]));}).assignTimestampsAndWatermarks(WatermarkStrategy.WaterSensorforMonotonousTimestamps().withTimestampAssigner(new SerializableTimestampAssignerWaterSensor() {Overridepublic long extractTimestamp(WaterSensor element, long recordTimestamp) {return element.getTs() * 1000;}}));s1.join(s2).where(WaterSensor::getId).equalTo(WaterSensor::getId).window(TumblingEventTimeWindows.of(Time.seconds(5))) // 必须使用窗口.apply(new JoinFunctionWaterSensor, WaterSensor, String() {Overridepublic String join(WaterSensor first, WaterSensor second) throws Exception {return first: first , second: second;}}).print();try {env.execute();} catch (Exception e) {e.printStackTrace();}}
}运行结果
三、Interval Join
间隔流join(Interval Join), 是指使用一个流的数据按照key去join另外一条流的指定范围的数据. 如下图: 橙色的流去join绿色的流.范围是由橙色流的event-time lower bound和event-time upper bound来决定的. orangeElem.ts lowerBound greenElem.ts orangeElem.ts upperBound Interval Join只支持event-time 必须是keyBy之后的流才可以interval join
package com.lyh.flink12;
import com.lyh.bean.WaterSensor; import org.apache.flink.api.common.eventtime.SerializableTimestampAssigner; import org.apache.flink.api.common.eventtime.WatermarkStrategy; import org.apache.flink.configuration.Configuration; import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator; import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment; import org.apache.flink.streaming.api.functions.co.ProcessJoinFunction; import org.apache.flink.streaming.api.windowing.time.Time; import org.apache.flink.table.planner.expressions.In; import org.apache.flink.util.Collector;
import java.time.Duration;public class Sql_Join_Windows_Interval{public static void main(String[] args) {StreamExecutionEnvironment env StreamExecutionEnvironment.createLocalEnvironmentWithWebUI(new Configuration());env.setParallelism(2);SingleOutputStreamOperatorWaterSensor s1 env.socketTextStream(hadoop100, 8888).map(value - {String[] data value.split(,);return new WaterSensor(data[0],Long.valueOf(data[1]),Integer.valueOf(data[2]));}).assignTimestampsAndWatermarks(WatermarkStrategy.WaterSensorforBoundedOutOfOrderness(Duration.ofSeconds(2)).withTimestampAssigner(new SerializableTimestampAssignerWaterSensor() {Overridepublic long extractTimestamp(WaterSensor element, long timestamp) {return element.getTs();}}));SingleOutputStreamOperatorWaterSensor s2 env.socketTextStream(hadoop100, 9999).map(value - {String[] data value.split(,);return new WaterSensor(data[0],Long.valueOf(data[1]),Integer.valueOf(data[2]));}).assignTimestampsAndWatermarks(WatermarkStrategy.WaterSensorforBoundedOutOfOrderness(Duration.ofSeconds(2)).withTimestampAssigner(new SerializableTimestampAssignerWaterSensor() {Overridepublic long extractTimestamp(WaterSensor element, long timestamp) {return element.getTs();}}));s1.keyBy(WaterSensor::getId).intervalJoin(s2.keyBy(WaterSensor::getId)).between(Time.seconds(-2),Time.seconds(3)).process(new ProcessJoinFunctionWaterSensor, WaterSensor, String() {Overridepublic void processElement(WaterSensor left,WaterSensor right,Context ctx,CollectorString out) throws Exception {out.collect(left , right);}}).print();try{env.execute();} catch (Exception e){e.printStackTrace();}}}运行结果
