spark--actions算子--count

import org.apache.spark.{SparkConf, SparkContext}/**  * Created by liupeng on 2017/6/16.  */object A_count {  System.setProperty("hadoop.home.dir","F:\\hadoop-2.6.5")  def main(args: Array[String]): Unit = {    val conf = new SparkConf().setAppName("count_test").setMaster("local")    val sc = new SparkContext(conf)    //准备一下数据    val nameList : List[Int] = List(1,2,3,4,5)    val numbers = sc.parallelize(nameList)    //计算数据集的数据个数，一般都是统计内部元素的个数。    val num = numbers.count()    println(num)  }}

运行结果：

5