spark--actions算子--takeOrdered

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

/**
  * Created by liupeng on 2017/6/16.
  */
object A_takeOrdered {
  System.setProperty("hadoop.home.dir","F:\\hadoop-2.6.5")

  def main(args: Array[String]): Unit = {
    val conf = new SparkConf().setAppName("takeOrdered_test").setMaster("local")
    val sc = new SparkContext(conf)
    //准备一下数据
    val nameList: List[String] = List("c", "d", "a", "e", "f", "k")
    val numbers = sc.parallelize(nameList)
    //基于内置的排序规则或者自定义的排序规则排序，返回前n个元素
    val num = numbers.takeOrdered(3)
    for (x <- num) {
      println(x)
    }
  }
}

运行结果：

a
c
d