AllLogicInShutdownHook.scala

package com.gabrieljones

import java.util.concurrent.{Executors, ScheduledFuture}
import scala.sys.ShutdownHookThread

object AllLogicInShutdownHook {
  def main(args: Array[String]): Unit = {
// schedule executor

    println("Adding Hook...")
    val hook = sys.addShutdownHook {
      println(s"${Thread.currentThread()} Starting...")
      val thread = new Thread(() => {
        println(s"${Thread.currentThread()} Starting...")
        println(s"${Thread.currentThread()} Sleeping...")
        Thread.sleep(10000)
        println(s"${Thread.currentThread()} Done")
      })
      thread.start()
      val scheduler = Executors.newScheduledThreadPool(1)
      val f: ScheduledFuture[_] = scheduler.schedule({ () =>
        println(s"${Thread.currentThread()} Starting...")
        println(s"${Thread.currentThread()} Sleeping...")
        Thread.sleep(5000)
        println(s"${Thread.currentThread()} Done")
      }: Runnable, 20, java.util.concurrent.TimeUnit.SECONDS)
      println(s"${Thread.currentThread()} Sleeping...")
      Thread.sleep(5000)
//      println(s"${hook} -> ${thread} Joining...")
//      thread.join()
      println(s"${Thread.currentThread()} Getting $f...")
      println(f.get())
      println(s"${Thread.currentThread()} Got $f")
      println(s"${Thread.currentThread()} Done")
    }
    println(s"$hook Added")
    println(s"${Thread.currentThread()} Exiting...")
    System.exit(0)
  }
}