Flink1.14实战Flink DataStream 算子 FlatMap

Posted 2022-04-11 吕布辕门

FlatMap

DataStream → DataStream

接受一个元素并产生零个、一个或多个元素。将句子拆分为单词的 flatmap 函数：

package quick;

import org.apache.flink.api.common.functions.FlatMapFunction;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.util.Collector;

public class FlatMapExample 
    public static void main(String[] args) throws Exception 

        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        DataStream<String> dataStream = env
                .fromElements("Flink Spark Storm","Flink Flink Flink")
                .flatMap(new FlatMapFunction<String, String>() 
                    @Override
                    public void flatMap(String value, Collector<String> out)
                            throws Exception 
                        for(String word: value.split(" "))
                            out.collect(word);
                        
                    
                );

        dataStream.print();

        env.execute("FlatMapExample job");

    

修改pom

<version>1.0.1</version>
<mainClass>quick.FlatMapExample </mainClass>

然后，将打包应用程序提交，Flink 的Web UI来提交作业监控集群的状态和正在运行的作业。