IDEA中运行Spark

   IDEA中运行Spark有两种方式本地模式和远程模式。

1.本地模式

   本地Spark程序调试需要使用local提交模式，即将本机当做运行环境，Master和Worker都为本机。

1. Maven依赖

<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>4.0.0modelVersion>

    <groupId>com.edwingroupId>
    <artifactId>CoreWordCountartifactId>
    <version>1.0-SNAPSHOTversion>
    <dependencies>
        <dependency>
            <groupId>org.scala-langgroupId>
            <artifactId>scala-libraryartifactId>
            <version>2.11.8version>
        dependency>

        <dependency>
            <groupId>org.apache.sparkgroupId>
            <artifactId>spark-core_2.11artifactId>
            <version>2.1.1version>
            
        dependency>
        <dependency>
            <groupId>org.apache.hadoopgroupId>
            <artifactId>hadoop-clientartifactId>
            <version>2.7.2version>
            
        dependency>

    dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.scala-toolsgroupId>
                <artifactId>maven-scala-pluginartifactId>
                <version>2.15.2version>
                <executions>
                    <execution>
                        <id>scala-compile-firstid>
                        <goals>
                            <goal>compilegoal>
                        goals>
                        <configuration>
                            <includes>
                                <include>**/*.scalainclude>
                            includes>
                        configuration>
                    execution>
                    <execution>
                        <id>scala-test-compileid>
                        <goals>
                            <goal>testCompilegoal>
                        goals>
                    execution>
                executions>
            plugin>
        plugins>
    build>  
project>

2. Scala代码

package main

import org.apache.spark.{SparkConf, SparkContext}

object WordCount {
  def main(args: Array[String]): Unit = {
    //创建SparkConf()并设置App名称
    val conf = new SparkConf().setMaster("local[*]").setAppName("WC")
    //创建SparkContext，该对象是提交spark App的入口
    val sc = new SparkContext(conf)
    //使用sc创建RDD并执行相应的transformation和action
    sc.textFile("D:\\words.txt")
      .flatMap(_.split(" "))
      .map((_, 1))
      .reduceByKey(_+_, 1)
      .sortBy(_._2, false)
      .saveAsTextFile("D:\\output")
    //停止sc，结束该任务
    sc.stop()
  }
}

2.远程调试

   通过IDEA进行远程调试，主要是将IDEA作为Driver来提交应用程序。

package main

import org.apache.spark.{SparkConf, SparkContext}

object WordCount {
  def main(args: Array[String]): Unit = {
    //创建SparkConf()并设置App名称
    val conf = new SparkConf()
      .setMaster("spark://L0:7077")
      .setAppName("WordCount")
      .setJars(Array("D:\\\\CoreWordCount-1.0-SNAPSHOT.jar"))
      .setIfMissing("spark.driver.host", "192.168.191.130")
    //创建SparkContext，该对象是提交spark App的入口
    val sc = new SparkContext(conf)
    //使用sc创建RDD并执行相应的transformation和action
    sc.textFile("hdfs://l0:8020/words.txt")
      .flatMap(_.split(" "))
      .map((_, 1))
      .reduceByKey(_+_, 1)
      .sortBy(_._2, false)
      .saveAsTextFile("hdfs://l0:8020/output")
    //停止sc，结束该任务
    sc.stop()

  }
}