quick sort with using scala.concurrent.forkjoin

Main.scala

import scala.concurrent.forkjoin.ForkJoinPool
import scala.concurrent.forkjoin.RecursiveTask

object Main {
  def main(args: Array[String]) {
    val pool = new ForkJoinPool()
    println(s"${Thread.currentThread.getId}: unsorted=" + args.mkString(", "))
    val sorted = pool.invoke(new QuickSortingTask(args))
    println(s"${Thread.currentThread.getId}: sorted=" + sorted.mkString(", "))
  }
}

class QuickSortingTask(data: Seq[String]) extends RecursiveTask[Seq[String]] {
  override def compute(): Seq[String] = {
    println(s"${Thread.currentThread.getId}: data=" + data.mkString(", "))
    if (data.length < 2) {
      data
    } else {
      val pivot = data.head
      val unsorted = data.tail
      val lhs = new QuickSortingTask(unsorted.filter(_ < pivot))
      val rhs = new QuickSortingTask(unsorted.filter(_ >= pivot))
      rhs.fork
      lhs.invoke ++ Seq(pivot) ++ rhs.join
    }
  }
}