一.引入Flink的目的
- 低延迟
- 高吞吐
- 结果的准确性和良好的容错性
二、例子(实现wordCount)
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package com.xesonline.demo import org.apache.flink.api.scala.{DataSet, ExecutionEnvironment} import org.apache.flink.api.scala._ /** * @Classname WordCount * @Description * @Date 2020/11/3 3:06 下午 * @Created by jinping */ //批处理的wordCount object WordCount { def main(args: Array[String]){ //创建执行环境 val env:ExecutionEnvironment= ExecutionEnvironment.getExecutionEnvironment; val inputPath : String = "/Users/jinping/Desktop/flink/ss-flink-scala/src/main/resources/word.txt"; val inputDataSet : DataSet[String] = env.readTextFile(inputPath); //对数据进行转换处理，先分词 val resultDataset:DataSet[(String,Int)] = inputDataSet .flatMap(.split(" ")) .map((,1)) .groupBy(0)//以第一个元素作为key进行分组 .sum(1); resultDataset.print(); } }
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