简单的构建一个Apache Spark应用程序
开发环境准备:
运行在Windows
jdk1.8和maven环境
pom如下:
<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/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>SparkDemo</groupId> <artifactId>SparkDemo</artifactId> <version>1.0-SNAPSHOT</version> <inceptionYear>2008</inceptionYear> <properties> <scala.version>2.11.1</scala.version> </properties> <repositories> <repository> <id>scala-tools.org</id> <name>Scala-Tools Maven2 Repository</name> <url>http://scala-tools.org/repo-releases</url> </repository> </repositories> <pluginRepositories> <pluginRepository> <id>scala-tools.org</id> <name>Scala-Tools Maven2 Repository</name> <url>http://scala-tools.org/repo-releases</url> </pluginRepository> </pluginRepositories> <dependencies> <dependency> <groupId>org.scala-lang</groupId> <artifactId>scala-library</artifactId> <version>${scala.version}</version> </dependency> <!-- https://mvnrepository.com/artifact/org.apache.spark/spark-core --> <dependency> <groupId>org.apache.spark</groupId> <artifactId>spark-core_2.11</artifactId> <version>2.2.0</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.4</version> <scope>test</scope> </dependency> <dependency> <groupId>org.specs</groupId> <artifactId>specs</artifactId> <version>1.2.5</version> <scope>test</scope> </dependency> </dependencies> <build> <sourceDirectory>src/main/scala</sourceDirectory> <testSourceDirectory>src/test/scala</testSourceDirectory> <plugins> <plugin> <groupId>org.scala-tools</groupId> <artifactId>maven-scala-plugin</artifactId> <executions> <execution> <goals> <goal>compile</goal> <goal>testCompile</goal> </goals> </execution> </executions> <configuration> <scalaVersion>${scala.version}</scalaVersion> <args> <arg>-target:jvm-1.5</arg> </args> </configuration> </plugin> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-eclipse-plugin</artifactId> <configuration> <downloadSources>true</downloadSources> <buildcommands> <buildcommand>ch.epfl.lamp.sdt.core.scalabuilder</buildcommand> </buildcommands> <additionalProjectnatures> <projectnature>ch.epfl.lamp.sdt.core.scalanature</projectnature> </additionalProjectnatures> <classpathContainers> <classpathContainer>org.eclipse.jdt.launching.JRE_CONTAINER</classpathContainer> <classpathContainer>ch.epfl.lamp.sdt.launching.SCALA_CONTAINER</classpathContainer> </classpathContainers> </configuration> </plugin> </plugins> </build> <reporting> <plugins> <plugin> <groupId>org.scala-tools</groupId> <artifactId>maven-scala-plugin</artifactId> <configuration> <scalaVersion>${scala.version}</scalaVersion> </configuration> </plugin> </plugins> </reporting> </project>
工作目录:
编写Spark程序:
创建WordCount程序:
package SparkDemo import org.apache.spark.{SparkConf, SparkContext} import org.apache.spark.rdd.RDD /** * @Author: luomo * @CreateTime: 2019/10/24 * @Description:WordCount */ object WordCount { def main(args: Array[String]): Unit = { //配置文件 val conf = new SparkConf(). setAppName("wordcount") // 运行时候的作业名称 .setMaster("local") //上下文 拿着Conf信息创建出来 写spark应用程序的对象 通往集群的入口 val sc = new SparkContext(conf) //传入文件对象 返回RDD集合 val input = sc.textFile("E:///test.txt") //对文件行数据 按照空格切割 返回RDD集合 得到每个单词 val lines = input.flatMap(line => line.split(" ")) //统计单词数量 计数 得到RDD集合 按照相同的Key先分组,之后再对组内的Value进行操作 val count = lines.map(word => (word, 1)).reduceByKey{case (x, y) => x + y} //将结果遍历打印到控制台 count.foreach(x =>{ println(x) }) //将结果输出到文件中 val output = count.saveAsTextFile("E:///wordCount") //关闭流 在内存中释放这个spark对象 //sc.stop() } }
运行程序如图: