多线程按顺序打印数字

package com.youzu.got.world

import com.google.common.base.Stopwatch

@Volatile
var runNum = 0
var threadNum = 3
var maxNum = 300000


class MyThread(private val threadName: String, var curNum: Int) : Thread() {

  override fun run() {

    while (true) {
      if (curNum <= runNum) {
        println("$threadName : ${runNum + 1}")
        curNum += threadNum
        runNum++
      }
      if (runNum > maxNum) {
        break
      }
    }
  }
}

fun main() {
  var list = arrayListOf<Thread>()


  for (n in 0 until threadNum) {
    val thread = MyThread("threadName_$n", n)
    list.add(thread)
  }

  var watch = Stopwatch.createStarted()
  list.forEach {
    it.start()
  }

  list.forEach {
    it.join()
  }
  watch.stop()
  println(watch)

}