1、

示例代码

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

object Test {
  def main(args: Array[String]) {
    val conf = new SparkConf().setAppName("join").setMaster("local[4]")
    val sc = new SparkContext(conf)
    val rdd1 = sc.parallelize(Seq(1,2,3))
    val rdd2 = sc.parallelize(Seq(2,3,4))

    val rdd3=rdd1.map(x=>(x,1))
    val rdd4=rdd2.map(x=>(x,2))

    val rdd5=rdd3.join(rdd4)
    
    print("rdd3: ")
    rdd3.collect().foreach(x=>print(x))
    println()
    print("rdd4: ")
    rdd4.collect().foreach(x=>print(x))
    println()
    print("rdd5: ")
    rdd5.collect().foreach(x=>print(x))
    println()

  }
}

输出结果：
rdd3: (1,1)(2,1)(3,1)
rdd4: (2,2)(3,2)(4,2)
rdd5: (2,(1,2))(3,(1,2))

一个创业中的苦逼程序员