1.pom.xml 文件引用jar包，jar包冲突可能会启动不了。flink-client 必须

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.test</groupId>
    <artifactId>flinktest</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <flink.version>1.15.0</flink.version>
        <scala.version>2.12.7</scala.version>
        <redis.version>3.2.0</redis.version>
        <hbase.version>1.3.3</hbase.version>
        <mysql.version>5.1.44</mysql.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-scala_2.12</artifactId>
            <version>1.14.4</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-streaming-scala_2.12</artifactId>
            <version>1.14.4</version>
        </dependency>

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-clients_2.12</artifactId>
            <version>1.14.4</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <!-- 在maven项目中既有java又有scala代码时配置 maven-scala-plugin 插件打包时可以将两类代码一起打包 -->
            <plugin>
                <groupId>org.scala-tools</groupId>
                <artifactId>maven-scala-plugin</artifactId>
                <version>2.15.2</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                            <goal>testCompile</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>

            <!-- maven 打jar包需要插件 -->
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <version>2.4</version>
                <configuration>
                    <!-- 设置false后是去掉 MySpark-1.0-SNAPSHOT-jar-with-dependencies.jar 后的 “-jar-with-dependencies” -->
                    <!--<appendAssemblyId>false</appendAssemblyId>-->
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                </configuration>
                <executions>
                    <execution>
                        <id>make-assembly</id>
                        <phase>package</phase>
                        <goals>
                            <goal>assembly</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>



</project>

读取文本的wordcount

object FlinkDay1 {

  def main(args: Array[String]): Unit = {

//    val env = StreamExecutionEnvironment.getExecutionEnvironment

    val env = ExecutionEnvironment.getExecutionEnvironment;

    env.setParallelism(2)

    val initStream =  env.readTextFile("C:\\Users\\shenyingkui\\Desktop\\datatest.txt");

    val wordStream = initStream.flatMap(_.split(" "))
    wordStream.print()

    val pairStream = wordStream.map((_,1))
    val keyByStream = pairStream.groupBy(0)

    val restStream = keyByStream.sum(1)

    restStream.print()


  }
}

stream 流，通过socket 的wordcount

import org.apache.flink.streaming.api.scala.StreamExecutionEnvironment
import org.apache.flink.streaming.api.scala._
object StreamDemo {

  def main(args: Array[String]): Unit = {
    val environment = StreamExecutionEnvironment.getExecutionEnvironment
    val datastream = environment.socketTextStream("192.168.71.106",9998)
    datastream.print()
    datastream.map((_,1)).keyBy(0).sum(1).print()

    environment.execute("first stream")
  }
}

  datastream.map((_,1)).keyBy(_._1).countWindow(10,2).reduce(new ReduceFunction[(String, Int)] {
      override def reduce(t: (String, Int), t1: (String, Int)): (String, Int) = {
        (t1._1,t1._2+t._2)
      }
    }) .print()//滚动窗口

  datastream.flatMap((_.split(" "))).map((_,1)).keyBy((_,1)).reduce((v:(String,Int) ,v1:(String,Int) )=>{
      (v._1,v._2+v1._2)
    }).print()