一 Flink的核心组件
1.1 client
1.将数据流程图DataFlow发送给JobManager。
1.2 JobManager
1.收集client的DataFlow图,将图分解成一个个的task任务,并返回状态更新数据给client
2.JobManager负责作业调度,收集TaskManager的Heartbeat和统计信息。
1.3 TaskManager
1.将每一个task任务放到一个TaskSlot槽中
2.TaskManager 之间以流的形式进行数据的传输。
二 Flink的集群搭建
2.1 独立集群
2.1.1 上传解压配置环境变量
1.解压 tar -zxvf flink-1.15.2-bin-scala_2.12.tgz -C ../
2.配置环境变量
# 配置环境变量
vim /etc/profileexport FLINK_HOME=/usr/local/soft/flink-1.15.2
export PATH=$PATH:$FLINK_HOME/binsource /etc/profile
2.1.2 修改配置文件
1.修改flink-conf.yaml
jobmanager.rpc.address: master
jobmanager.bind-host: 0.0.0.0
taskmanager.bind-host: 0.0.0.0
taskmanager.host: localhost # noe1和node2需要单独修改
taskmanager.numberOfTaskSlots: 4
rest.address: master
rest.bind-address: 0.0.0.0
2.修改masters
master:8081
3.修改workers
node1
node2
2.1.3 同步到所有节点
1.同步
scp -r flink-1.15.2 node1:`pwd`
scp -r flink-1.15.2 node2:`pwd`
2.修改子节点的flink-conf.yaml文件中的taskmanager.host
taskmanager.host: node1
taskmanager.host: node2
2.1.4 启动与关闭集群
1.启动
start-cluster.sh
2.看是否成功,打开web ui界面
http://master:8081
3.关闭集群
stop-cluster.sh
2.1.5 提交任务
1.将代码打包到服务器中提交
1.启动命令
flink run -c com.shujia.flink.core.Demo1StreamWordCount flink-1.0.jar
com.shujia.flink.core.Demo1StreamWordCount:主类名
flink-1.0.jar:jar包名
2.查看web界面
3.查看结果
4.关闭任务
2.web界面提交任务
1.提交
2.相关配置
2.2 Flink on Yarn
2.2.1 整合
1.在环境变量中配置HADOOP_CLASSSPATH
vim /etc/profileexport HADOOP_CLASSPATH=`hadoop classpath`source /etc/profile
2.2.2 Application Mode
1、将任务提交到yarn上运行,yarn会为每一个flink地任务启动一个jobmanager和一个或者多个taskmanasger
2、代码main函数不再本地运行,dataFlow不再本地构建,如果代码报错在本地看不到详细地错误日志
1.启动命令
flink run-application -t yarn-application -c com.shujia.flink.core.Demo1StreamWordCount flink-1.0.jar
flink run-application -t yarn-application -c:任务命令名
com.shujia.flink.core.Demo1StreamWordCount:主类名
flink-1.0.jar:jar包名
2.查看界面
点击这个,直接跳转到Flink的web界面
2.2.3 Per-Job Cluster Mode
1、将任务提交到yarn上运行,yarn会为每一个flink地任务启动一个jobmanager和一个或者多个taskmanasger
2、代码地main函数在本地启动,在本地构建dataflow,再将dataflow提交给jobmanager,如果代码报错再本地可以烂到部分错误日志
1.启动命令
flink run -t yarn-per-job -c com.shujia.flink.core.Demo1StreamWordCount flink-1.0.jar
flink run -t yarn-per-job -c:命令名
com.shujia.flink.core.Demo1StreamWordCount:主类名
flink-1.0.jar:jar包名
2.界面跟Application Mode一样
2.3.4 Session Mode
1、先再yarn中启动一个jobmanager, 不启动taskmanager
2、提交任务地时候再动态申请taskmanager
3、所有使用session模式提交的任务共享同一个jobmanager
4、类似独立集群,只是集群在yarn中启动了,可以动态申请资源
5、一般用于测试
1.先启动会话集群
yarn-session.sh -d
启动过后出现这个,一个是任务编码application_1717379968853_0003
另一个是web界面,复制可以打开
2.提交任务
命令提交:
flink run -t yarn-session -Dyarn.application.id=application_1717379968853_0003 -c com.shujia.flink.core.Demo1StreamWordCount flink-1.0.jar
Dyarn.application.id=application_1717379968853_0003:这个是启动会话集群给的
com.shujia.flink.core.Demo1StreamWordCount:主类名
flink-1.0.jar:jar包名
web界面提交:跟Application Mode的web提交一模一样
三 并行度
3.1 设置并行度
3.1.1 代码中设置
1.代码中不设置,默认的并行度数量是配置文件里面的
2.代码中配置
env.setParallelism(2)
3.1.2 提交任务中设置
1.加一个参数 -p 并行度数量
例如:
flink run -t yarn-session -p 3 -Dyarn.application.id=application_1717379968853_0003 -c com.shujia.flink.core.Demo1StreamWordCount flink-1.0.jar
2.或者在ui界面中设置
3.1.3 配置文件中设置
1.这个一般不用
在flink-conf.yaml修改配置
3.1.4 每一个算子单独设置
在代码中使用算子时候后面可以设置并行度,但是这种不用
3.1.4 优先级
代码>提交任务中配置>配置文件
3.2 共享资源
1、flink需要资源的数量和task数量无关
2、一个并行度对应一个资源(slot)
3、上游task的下游task共享同一个资源
3.3 并行度设置原则
1.实时计算的任务并行度取决于数据的吞吐量
2、聚合计算(有shuffle)的代码一个并行度大概一秒可以处理10000条数据左右
3、非聚合计算是,一个并行度大概一秒可以处理10万条左右
四 事件时间
4.1 event time
数据产生的时间,数据中有一个时间字段,使用数据的时间字段触发计算,代替真实的时间,可以反应数据真实发生的顺序,计算更有意义
4.1.1 数据时间无乱序
1.解析数据,分析哪个数据是数据时间
2.指定时间字段
forMonotonousTimestamps():单调递增。数据时间只能是往上增的
tsDS.assignTimestampsAndWatermarks(WatermarkStrategy
//指定水位线生产策略,水位线等于最新一条数据的时间戳,如果数据乱序可能会丢失数据
.<Tuple2<String, Long>>forMonotonousTimestamps()
//指定时间字段
.withTimestampAssigner((event, ts) -> event.f1));
2.完整代码如下
package com.shujia.flink.core;import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.WindowedStream;
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;
import org.apache.flink.streaming.api.windowing.windows.TimeWindow;import java.time.Duration;public class Demo5EventTime {public static void main(String[] args)throws Exception {/** 事件时间:数据中有一个时间字段,使用数据的时间字段触发计算,代替真实的时间,可以反应数据真实发生的顺序,计算更有意义*//*java,1717395300000java,1717395301000java,1717395302000java,1717395303000java,1717395304000java,1717395305000*/StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();env.setParallelism(1);DataStream<String> linesDS = env.socketTextStream("master", 8888);//解析数据DataStream<Tuple2<String, Long>> tsDS = linesDS.map(line -> {String[] split = line.split(",");String word = split[0];long ts = Long.parseLong(split[1]);return Tuple2.of(word, ts);}, Types.TUPLE(Types.STRING, Types.LONG));/** 指定时间字段和水位线生成策略*/DataStream<Tuple2<String, Long>> assDS = tsDS.assignTimestampsAndWatermarks(WatermarkStrategy//指定水位线生产策略,水位线等于最新一条数据的时间戳,如果数据乱序可能会丢失数据.<Tuple2<String, Long>>forMonotonousTimestamps()//指定时间字段.withTimestampAssigner((event, ts) -> event.f1));/**每隔5秒统计单词的数量*/DataStream<Tuple2<String, Integer>> kvDS = assDS.map(kv -> Tuple2.of(kv.f0, 1), Types.TUPLE(Types.STRING, Types.INT));KeyedStream<Tuple2<String, Integer>, String> keyByDS = kvDS.keyBy(kv -> kv.f0);//TumblingEventTimeWindows:滚动的事件时间窗口WindowedStream<Tuple2<String, Integer>, String, TimeWindow> windowDS = keyByDS.window(TumblingEventTimeWindows.of(Time.seconds(5)));windowDS.sum(1).print();env.execute();}
}
3.结果分析
上面代码是以5秒作为一个滚动的事件时间窗口。不包括第五秒,左闭右开。
窗口的触发条件:水位线大于等于窗口的结束时间;窗口内有数据
水位线:等于最新一条数据的时间戳
比如说0-5-10-15-20.0-5是一个窗口,5-10是一个窗口,且窗口里面有数据才能被计算,如果这个窗口里面出现了不存在这个时间的事件,则不会被处理
输入的事件时间是乱序的,他丢失第四次输出的。
4.1.2 数据时间乱序
1.水位线前移,使用forBoundedOutOfOrderness里面传入前移的时间
tsDS.assignTimestampsAndWatermarks(WatermarkStrategy
//水位线前移时间(数据最大乱序时间)
.<Tuple2<String, Long>>forBoundedOutOfOrderness(Duration.ofSeconds(5))
//指定时间字段
.withTimestampAssigner((event, ts) -> event.f1));
2.完整代码
package com.shujia.flink.core;import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.WindowedStream;
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;
import org.apache.flink.streaming.api.windowing.windows.TimeWindow;import java.time.Duration;public class Demo5EventTime {public static void main(String[] args)throws Exception {/** 事件时间:数据中有一个时间字段,使用数据的时间字段触发计算,代替真实的时间,可以反应数据真实发生的顺序,计算更有意义*/StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();/*java,1717395301000java,1717395302000java,1717395303000java,1717395304000java,1717395305000java,1717395307000java,1717395308000java,1717395311000java,1717395313000java,1717395315000*/env.setParallelism(1);DataStream<String> linesDS = env.socketTextStream("master", 8888);//解析数据DataStream<Tuple2<String, Long>> tsDS = linesDS.map(line -> {String[] split = line.split(",");String word = split[0];long ts = Long.parseLong(split[1]);return Tuple2.of(word, ts);}, Types.TUPLE(Types.STRING, Types.LONG));/** 指定时间字段和水位线生成策略*/DataStream<Tuple2<String, Long>> assDS = tsDS.assignTimestampsAndWatermarks(WatermarkStrategy//指定水位线生产策略,水位线等于最新一条数据的时间戳,如果数据乱序可能会丢失数据
// .<Tuple2<String, Long>>forMonotonousTimestamps()//水位线前移时间(数据最大乱序时间).<Tuple2<String, Long>>forBoundedOutOfOrderness(Duration.ofSeconds(5))//指定时间字段.withTimestampAssigner((event, ts) -> event.f1));/**每隔5秒统计单词的数量*/DataStream<Tuple2<String, Integer>> kvDS = assDS.map(kv -> Tuple2.of(kv.f0, 1), Types.TUPLE(Types.STRING, Types.INT));KeyedStream<Tuple2<String, Integer>, String> keyByDS = kvDS.keyBy(kv -> kv.f0);//TumblingEventTimeWindows:滚动的事件时间窗口WindowedStream<Tuple2<String, Integer>, String, TimeWindow> windowDS = keyByDS.window(TumblingEventTimeWindows.of(Time.seconds(5)));windowDS.sum(1).print();env.execute();}
}
3.结果分析
我输入的如图所示,我代码设置了水位线前移5秒中,所以触发时间是10秒才触发任务,0-10秒里有4个0-5里面的数据,所以输出了4.为什么14000没有输出,因为14-5=9,他还没有到下一阶段的水位线。我再输出了16秒的,他就有结果了。
4.1.3 水位线对齐
1.当上游有多个task时,下游task会取上游task水位线的最小值,如果数据量小。水位线就很难对齐,窗口就不会触发计算。故要设置并行度,提前把task设定好。
2.如果不设置并行度,可能要输出很多事件才能触发计算。
4.2 processing time
1.处理时间:真实时间
2.这个代码是设置了滚动的处理时间窗口吗,每现实时间5秒中处理一下数据
package com.shujia.flink.core;import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.WindowedStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.windowing.assigners.TumblingProcessingTimeWindows;
import org.apache.flink.streaming.api.windowing.time.Time;
import org.apache.flink.streaming.api.windowing.windows.TimeWindow;public class Demo4ProcTime {public static void main(String[] args) throws Exception {StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();DataStream<String> wordsDS = env.socketTextStream("master", 8888);//转换成kvDataStream<Tuple2<String, Integer>> kvDS = wordsDS.map(word -> Tuple2.of(word, 1), Types.TUPLE(Types.STRING, Types.INT));//按照单词分组KeyedStream<Tuple2<String, Integer>, String> keyByDS = kvDS.keyBy(kv -> kv.f0);//划分窗口//TumblingProcessingTimeWindows:滚动的处理时间窗口WindowedStream<Tuple2<String, Integer>, String, TimeWindow> windowDS = keyByDS.window(TumblingProcessingTimeWindows.of(Time.seconds(5)));//统计单词的数量DataStream<Tuple2<String, Integer>> countDS = windowDS.sum(1);countDS.print();env.execute();}
}
五 窗口
5.1 time window
1.时间窗口有四种:
SlidingEventTimeWindows:滑动的事件时间窗口
SlidingProcessingTimeWindows: 滑动的处理时间窗口
TumblingEventTimeWindows:滚动的事件时间窗口
TumblingProcessingTimeWindows:滚动的处理时间窗口
2.滑动事件需要设置2个时间,一个设置窗口的大小,另一个是滚动的时间
package com.shujia.flink.window;import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.WindowedStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.windowing.assigners.SlidingEventTimeWindows;
import org.apache.flink.streaming.api.windowing.assigners.TumblingEventTimeWindows;
import org.apache.flink.streaming.api.windowing.time.Time;
import org.apache.flink.streaming.api.windowing.windows.TimeWindow;import java.time.Duration;public class Demo1TimeWindow {public static void main(String[] args)throws Exception {/** 事件时间:数据中有一个时间字段,使用数据的时间字段触发计算,代替真实的时间,可以反应数据真实发生的顺序,计算更有意义*/StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();/*java,1717395301000java,1717395302000java,1717395303000java,1717395304000java,1717395305000java,1717395307000java,1717395308000java,1717395311000java,1717395313000java,1717395315000*//**水位线对齐* 1、当上游有多个task时,下游task会取上游task水位线的最小值,如果数据量小。水位线就很难对齐,窗口就不会触发计算*/env.setParallelism(1);DataStream<String> linesDS = env.socketTextStream("master", 8888);//解析数据DataStream<Tuple2<String, Long>> tsDS = linesDS.map(line -> {String[] split = line.split(",");String word = split[0];long ts = Long.parseLong(split[1]);return Tuple2.of(word, ts);}, Types.TUPLE(Types.STRING, Types.LONG));/** 指定时间字段和水位线生成策略*/DataStream<Tuple2<String, Long>> assDS = tsDS.assignTimestampsAndWatermarks(WatermarkStrategy//指定水位线生产策略,水位线等于最新一条数据的时间戳,如果数据乱序可能会丢失数据
// .<Tuple2<String, Long>>forMonotonousTimestamps()//水位线前移时间(数据最大乱序时间).<Tuple2<String, Long>>forBoundedOutOfOrderness(Duration.ofSeconds(5))//指定时间字段.withTimestampAssigner((event, ts) -> event.f1));/**每隔5秒统计单词的数量*/DataStream<Tuple2<String, Integer>> kvDS = assDS.map(kv -> Tuple2.of(kv.f0, 1), Types.TUPLE(Types.STRING, Types.INT));KeyedStream<Tuple2<String, Integer>, String> keyByDS = kvDS.keyBy(kv -> kv.f0);/** SlidingEventTimeWindows:滑动的事件时间窗口* SlidingProcessingTimeWindows: 滑动的处理时间窗口* TumblingEventTimeWindows:滚动的事件时间窗口* TumblingProcessingTimeWindows:滚动的处理时间窗口* 滑动的时间窗口需要设置两个时间,第一个是窗口的大小,第二个是记录的时间,* 比如说(15,5),这是每5秒计算最近15秒内的数据*/WindowedStream<Tuple2<String, Integer>, String, TimeWindow> windowDS = keyByDS.window(SlidingEventTimeWindows.of(Time.seconds(15),Time.seconds(5)));windowDS.sum(1).print();env.execute();}
}
这个代码用的是滑动的事件时间窗口,我设置了每5秒钟计算最近15秒内的数据
5.2 count time
1.滚动的统计窗口:每个key隔多少数据计算一次
package com.shujia.flink.window;import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.*;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.windowing.windows.GlobalWindow;public class Demo2CountWindow {public static void main(String[] args) throws Exception {StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();DataStream<String> linesDS = env.socketTextStream("master", 8888);DataStream<Tuple2<String, Integer>> kvDS = linesDS.map(word -> Tuple2.of(word, 1), Types.TUPLE(Types.STRING, Types.INT));KeyedStream<Tuple2<String, Integer>, String> keyByDS = kvDS.keyBy(kv -> kv.f0);/** 统计窗口* countWindow(10):滚动的统计窗口, 每个key每隔10条数据计算一次* countWindow(10, 2): 滑动的统计窗口,每隔两条数据计算最近10条数据*/WindowedStream<Tuple2<String, Integer>, String, GlobalWindow> countWindowDS = keyByDS.countWindow(10, 2);countWindowDS.sum(1).print();env.execute();}
}
2.滑动的统计窗口:每隔多少数据计算最近的多少条数据
package com.shujia.flink.window;import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.*;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.windowing.windows.GlobalWindow;public class Demo2CountWindow {public static void main(String[] args) throws Exception{StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();DataStream<String> linesDS = env.socketTextStream("master", 8888);DataStream<Tuple2<String, Integer>> mapDS = linesDS.map(word -> Tuple2.of(word, 1), Types.TUPLE(Types.STRING, Types.INT));KeyedStream<Tuple2<String, Integer>, String> keyBy = mapDS.keyBy(kv -> kv.f0);WindowedStream<Tuple2<String, Integer>, String, GlobalWindow> countWindow = keyBy.countWindow(10,2);countWindow.sum(1).print();env.execute();}
}
5.3 session time
1.处理时间的会话窗口ProcessingTimeSessionWindows:对一个key,10秒内没有下一步数据开始计算。比如说我输入了 a*7次,然后等10秒输出结果是(a,7)。我再输入a*6次加一个aa,那么输出结果是(aa,1)与(a,6).
package com.shujia.flink.window;import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.WindowedStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.windowing.assigners.ProcessingTimeSessionWindows;
import org.apache.flink.streaming.api.windowing.time.Time;
import org.apache.flink.streaming.api.windowing.windows.TimeWindow;public class Demo3SessionWindow {public static void main(String[] args) throws Exception{StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();DataStream<String> linesDS = env.socketTextStream("master", 8888);DataStream<Tuple2<String, Integer>> mapDS = linesDS.map(word -> Tuple2.of(word, 1), Types.TUPLE(Types.STRING, Types.INT));KeyedStream<Tuple2<String, Integer>, String> keyBy = mapDS.keyBy(kv -> kv.f0);WindowedStream<Tuple2<String, Integer>, String, TimeWindow> window = keyBy.window(ProcessingTimeSessionWindows.withGap(Time.seconds(10)));window.sum(1).print();env.execute();}
}
2.事件时间的会话窗口EventTimeSessionWindows:根据数据的时间,对应同一个key,10秒内没有下一步数据开始计算
这个不常用
package com.shujia.flink.window;import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.WindowedStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.windowing.assigners.EventTimeSessionWindows;
import org.apache.flink.streaming.api.windowing.time.Time;
import org.apache.flink.streaming.api.windowing.windows.TimeWindow;import java.time.Duration;public class Demo4EventTimeSessionWindow {public static void main(String[] args) throws Exception{StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();/*
java,1685433130000
java,1685433131000
java,1685433132000
java,1685433134000
java,1685433135000
java,1685433137000
java,1685433139000
java,1685433149000
java,1685433155000
java,1685433170000*/env.setParallelism(1);DataStream<String> linesDS = env.socketTextStream("master", 8888);//解析数据DataStream<Tuple2<String, Long>> tsDS = linesDS.map(line -> {String[] split = line.split(",");String word = split[0];long ts = Long.parseLong(split[1]);return Tuple2.of(word, ts);}, Types.TUPLE(Types.STRING, Types.LONG));/** 指定时间字段和水位线生成策略*/DataStream<Tuple2<String, Long>> assDS = tsDS.assignTimestampsAndWatermarks(WatermarkStrategy//水位线前移时间(数据最大乱序时间).<Tuple2<String, Long>>forBoundedOutOfOrderness(Duration.ofSeconds(5))//指定时间字段.withTimestampAssigner((event, ts) -> event.f1));/**每隔5秒统计单词的数量*/DataStream<Tuple2<String, Integer>> kvDS = assDS.map(kv -> Tuple2.of(kv.f0, 1), Types.TUPLE(Types.STRING, Types.INT));KeyedStream<Tuple2<String, Integer>, String> keyByDS = kvDS.keyBy(kv -> kv.f0);/** EventTimeSessionWindows:事件时间的会话窗口*/WindowedStream<Tuple2<String, Integer>, String, TimeWindow> windowDS = keyByDS.window(EventTimeSessionWindows.withGap(Time.seconds(10)));windowDS.sum(1).print();env.execute(); }
}
5.4 process与窗口结合
1.设置了窗口过后的DS后面用process算子,他里面传入的是实现ProcessWindowFunction中的抽象方法process的对象,这个抽象类里面传的是4个参数(IN, OUT, KEY, W),输入的类型,输出的类型,key的类型,以及窗口类型。窗口类型是三大窗口的其中之一。
2.process方法里面,第一个参数是key,第二个参数是flink的环境连接对象。第三个参数是kv的键值对,第四个参数是发送的对象
代码如下
package com.shujia.flink.window;import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.*;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.windowing.ProcessWindowFunction;
import org.apache.flink.streaming.api.windowing.assigners.TumblingProcessingTimeWindows;
import org.apache.flink.streaming.api.windowing.time.Time;
import org.apache.flink.streaming.api.windowing.windows.TimeWindow;
import org.apache.flink.util.Collector;public class Demo5WindowProcess {public static void main(String[] args) throws Exception{StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();DataStream<String> linesDS = env.socketTextStream("master", 8888);SingleOutputStreamOperator<Tuple2<String, Integer>> kvDS = linesDS.map(line -> {String[] lines = line.split(",");String clazz = lines[4];int age = Integer.parseInt(lines[2]);return Tuple2.of(clazz, age);}, Types.TUPLE(Types.STRING, Types.INT));KeyedStream<Tuple2<String, Integer>, String> keyBy = kvDS.keyBy(kv -> kv.f0);WindowedStream<Tuple2<String, Integer>, String, TimeWindow> window = keyBy.window(TumblingProcessingTimeWindows.of(Time.seconds(5)));DataStream<Tuple2<String, Double>> process = window.process(new ProcessWindowFunction<Tuple2<String, Integer>, Tuple2<String, Double>, String, TimeWindow>() {@Overridepublic void process(String clazz,ProcessWindowFunction<Tuple2<String, Integer>, Tuple2<String, Double>, String, TimeWindow>.Context context,Iterable<Tuple2<String, Integer>> elements,Collector<Tuple2<String, Double>> out) throws Exception {double sum_age = 0;int num = 0;for (Tuple2<String, Integer> element : elements) {sum_age += element.f1;num++;}double avg_age = sum_age / num;out.collect(Tuple2.of(clazz, avg_age));}});process.print();env.execute();}
}