spark wordcount案例

<?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.atguigu</groupId>
    <artifactId>Streaming</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <scala.version>2.11.8</scala.version>
        <spark.version>2.1.1</spark.version>

    </properties>

    <dependencies>
        <!--添加scala依赖-->
        <dependency>
            <groupId>org.scala-lang</groupId>
            <artifactId>scala-library</artifactId>
            <version>${scala.version}</version>
            <!--如果有provide存在，那么打包的时候该依赖不会打到jar包中.-->
        <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-core_2.11</artifactId>
            <version>${spark.version}</version>
            <scope>provided</scope>
        </dependency>
    <!--添加streaming的依赖-->
        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-streaming_2.11</artifactId>
            <version>${spark.version}</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>

     <build>
    <!--添加编译的支持-->

         <plugins>

             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.6.1</version>
                 <configuration>
                     <source>1.8</source>
                     <target>1.8</target>
                 </configuration>
             </plugin>
             <!--添加打jar包的支持工具-->
             <plugin>
                 <groupId>net.alchim31.maven</groupId>
                 <artifactId>scala-maven-plugin</artifactId>
                 <version>3.2.2</version>
                 <executions>
                     <execution>
                         <goals>
                             <goal>compile</goal>
                             <goal>testCompile</goal>
                         </goals>
                     </execution>
                 </executions>
             </plugin>
             <!--打包用的-->
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-assembly-plugin</artifactId>
                 <version>3.0.0</version>
                 <executions>
                     <execution>
                         <id>make-assembly</id>
                         <phase>package</phase>
                         <goals>
                             <goal>single</goal>
                         </goals>
                     </execution>
                 </executions>
                 <configuration>
                     <archive>
                         <manifest>
                             <mainClass>com.atguigu.streaming.StreamingWordCount</mainClass>
                         </manifest>
                     </archive>
                     <descriptorRefs>
                         <descriptorRef>jar-with-dependencies</descriptorRef>
                     </descriptorRefs>
                 </configuration>
             </plugin>
     </plugins>
     </build>
</project>

package com.atguigu.streaming

import org.apache.spark.SparkConf
import org.apache.spark.streaming.{Seconds, StreamingContext}

object StreamingWordCount {

  val sparkconf =new SparkConf().setAppName("StreamingWordCount").setMaster("local[4]")

  val ssc =new StreamingContext(sparkconf,Seconds(1))
  //从master01机器上的9099端口吧剬的获取输入的是文本数据
  val line =ssc.socketTextStream("hadoop102",9999)

  val words  =line.flatMap(_.split(" "))

  //将每一个单词转换成一个元组
  val pairs = words.map((_,1))

  //根据单词来统计相同单词出现的次数
  val result =pairs.reduceByKey(_+_)


  result.print()

  //启动
  ssc.start()

  //等待你的停止信号
  ssc.awaitTermination()

}

yum install nc.x86_64

OK，安装正常。但有的人可能会遇到：protocol not available这个提示

解决方法：

在根目录[root@izwz9cjwo2hniwcgi204gez ~]下依次输入下面三条命令
       1、yum erase nc

       2、wget http://vault.centos.org/6.6/os/x86_64/Packages/nc-1.84-22.el6.x86_64.rpm

       3、rpm -iUv nc-1.84-22.el6.x86_64.rpm

wget http://vault.centos.org/6.6/os/i386/Packages/nc-1.84-22.el6.i686.rpm

nc -lk 9999

bin/spark-submit  --class com.atguigu.streaming.StreamingWordCount bin/Streaming-1.0-SNAPSHOT-jar-with-dependencies.jar