flatMap功能不隻是wordcount,不知不覺用flatmap實作了hive的自帶函數explode功能

// 不知不覺用flatmap實作了hive的自帶函數explode功能。
import org.apache.spark.SparkConf
import org.apache.spark.SparkContext
import org.apache.spark.sql.SQLContext
import org.apache.spark.sql.RowFactory
import org.apache.spark.sql.Row
import org.apache.spark.sql.types.StructType
import scala.annotation.meta.field
import org.apache.spark.sql.types.StringType
import org.apache.spark.sql.types.StructField
import scala.annotation.meta.field
import org.apache.spark.sql.hive.HiveContext


object flatmapOption { 
  
  def main(args: Array[String]): Unit = {
    val conf = new SparkConf().setMaster("local[3]").setAppName("flatmapOption")
    
    val sc = new SparkContext(conf) 
 
    val  aa = Array("this_1|2|3|4")
    val bb = sc.parallelize(aa.toSeq, 1)
    
    bb.flatMap { line => {
      val prfix = line.split("_")(0)
      
      val back = line.split("_")(1).split("\\|")