03、IDEA下Spark

03、IDEA下Spark API编程

3.1 编程实现Word Count

3.1.1 创建Scala模块

3.1.2 添加maven支持，并引入spark依赖

<?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.oldboy</groupId>
<artifactId>myspark</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
 <dependency>
   <groupId>org.apache.spark</groupId>
   <artifactId>spark-core_2.11</artifactId>
   <version>2.1.0</version>
 </dependency>
</dependencies>
</project>

3.1.3 编写scala程序

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

/**
* Created by Administrator on 2018/5/8.
*/
object WordCountScala {
def main(args: Array[String]): Unit = {
 //1.创建spark配置对象
 val conf = new SparkConf()

 //设置App名称
 conf.setAppName("wcApp")
 //设置master
 conf.setMaster("local")

 //2.创建spark上下文件对象
 val sc = new SparkContext(conf)

 //3.加载文件
 val rdd1 = sc.textFile("d:/mr/1.txt")

 //4.压扁
 val rdd2 = rdd1.flatMap(_.split(" "))

 //5.标1成对
 val rdd3 = rdd2.map(w => (w,1))

 //6.化简
 val rdd4 = rdd3.reduceByKey(_ + _)

 //收集数据
 val arr = rdd4.collect()

 arr.foreach(println)
}
}

3.1.4 编写java程序

package com.oldboy.spark.java;

import org.apache.spark.SparkConf;
import org.apache.spark.api.java.JavaPairRDD;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.api.java.function.FlatMapFunction;
import org.apache.spark.api.java.function.Function2;
import org.apache.spark.api.java.function.PairFunction;
import scala.Tuple2;

import java.util.Arrays;
import java.util.Iterator;
import java.util.List;

/**
*
*/
public class WordCountJava {
public static void main(String[] args) {
 //1.创建配置对象
 SparkConf conf = new SparkConf() ;
 conf.setAppName("wcApp") ;
 conf.setMaster("local") ;

 //2.创建java版的上下文
 JavaSparkContext sc = new JavaSparkContext(conf) ;

 //3.加载文件
 JavaRDD<String> rdd1 = sc.textFile("d:/mr/1.txt");

 //4.压扁
 JavaRDD<String> rdd2 = rdd1.flatMap(new FlatMapFunction<String, String>() {
   public Iterator<String> call(String s) throws Exception {
     String[] arr = s.split(" ");
     return Arrays.asList(arr).iterator();
   }
 }) ;

 //5.标一成对
 JavaPairRDD<String,Integer> rdd3 
   = rdd2.mapToPair(new PairFunction<String, String, Integer>() {
     public Tuple2<String, Integer> call(String s) throws Exception {
       return new Tuple2<String, Integer>(s , 1);
     }
   }) ;

 //6.化简
 JavaPairRDD<String,Integer> rdd4 
   = rdd3.reduceByKey(new Function2<Integer, Integer, Integer>() {
     public Integer call(Integer v1, Integer v2) throws Exception {
       return v1 + v2;
     }
   }) ;

 //7.收集
 List<Tuple2<String,Integer>> list = rdd4.collect();

 for(Tuple2<String,Integer> t : list){
   System.out.println(t._1() + " : " + t._2);
 }
}
}

3.2 编程实现温度统计

3.2.1 创建Scala模块

3.2.2 添加maven，引入Spark依赖

<?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.oldboy</groupId>
  <artifactId>myspark</artifactId>
  <version>1.0-SNAPSHOT</version>
  <dependencies>
    <dependency>
      <groupId>org.apache.spark</groupId>
      <artifactId>spark-core_2.11</artifactId>
      <version>2.1.0</version>
    </dependency>
  </dependencies>
</project>

3.2.3 编写Scala程序

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

/**
 * Created by Administrator on 2018/5/8.
 */
object TempAggScala {
  def main(args: Array[String]): Unit = {
    //1.创建spark配置对象
    val conf = new SparkConf()

    //设置App名称
    conf.setAppName("TempAgg")
    //设置master
    conf.setMaster("local")

    //2.创建spark上下文件对象
    val sc = new SparkContext(conf)

    //3.加载文件
    val rdd1 = sc.textFile("d:/mr/temps.dat")

    //4.变换形成嵌套的元组
    val rdd2 = rdd1.flatMap(line=>{
      val arr = line.split(" ")
      (arr(0).toInt , (arr(1).toInt ,arr(1).toInt))
    })

    //5.化简
    val rdd3 = rdd2.reduceByKey((a,b)=>{
      import scala.math
      val max = math.max(a(0) , b(0))
      val min = math.min(a(1) , b(1))
      (max,min)
    })

    //6.收集数据
    val arr = rdd3.collect()
    arr.foreach(println)
  }
}

3.2.4 编写Java程序

package com.oldboy.spark.java;

import org.apache.spark.SparkConf;
import org.apache.spark.api.java.JavaPairRDD;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.api.java.function.Function2;
import org.apache.spark.api.java.function.PairFunction;
import scala.Tuple2;
import scala.Tuple4;

import java.util.List;

/**
  * 统计气温数据
  */
public class TempAggJava {
  public static void main(String[] args) {
    SparkConf conf = new SparkConf();
    conf.setAppName("tempAggJava");
    conf.setMaster("local") ;
    
    //创建JavaSparkContext对象
    JavaSparkContext sc = new JavaSparkContext(conf);

    //1.加载文件，返回JavaRDD对象
    JavaRDD<String> rdd1 = sc.textFile("d:/mr/temp.dat");

    //2.变换
    JavaPairRDD<Integer, Tuple4<Integer, Integer, Double, Integer>> rdd2 
      = rdd1.mapToPair(new PairFunction<String, 
                        Integer,
                        Tuple2<Integer,Integer>>() {
      public Tuple2<Integer, Tuple2<Integer, Integer>> call(String s) 
        throws Exception {
        String[] arr = s.split(" ");
        int year = Integer.parseInt(arr[0]) ;
        int temp = Integer.parseInt(arr[1]) ;
        return new Tuple2<Integer, Tuple2<Integer, Integer>>(year, 
                                       new Tuple2<Integer,Integer>(temp , temp)) ;
      }
    }) ;

    //3.聚合
    JavaPairRDD<Integer, Tuple4<Integer, Integer, Double, Integer>> rdd3 
      = rdd2.reduceByKey(
      new Function2<Tuple2<Integer, Integer>, 
            Tuple2<Integer, Integer>, 
            Tuple2<Integer, Integer>>() {
        public Tuple2<Integer, Integer> call(Tuple2<Integer, Integer> v1,
                                             Tuple2<Integer, Integer> v2) 
          throws Exception {
          int max = Math.max(v1._1(),v2._1()) ;
          int min = Math.min(v1._2(),v2._2()) ;
          return new Tuple2<Integer, Integer>(max, min) ;
        }
      }) ;

    //收集
    List<Tuple2<Integer, Tuple2<Integer, Integer>>> list = rdd3.collect();
    for(Tuple2<Integer, Tuple2<Integer, Integer>> t : list){
      System.out.println(t);
    }
  }
}