Scala example source code file (oneplacebuffer.scala)

This example Scala source code file (oneplacebuffer.scala) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Scala tags/keywords

an, array, empty, empty, full, full, initialization, int, int, mailbox, mailbox, oneplacebuffer, types

The Scala oneplacebuffer.scala source code

package examples

object oneplacebuffer {

  import scala.concurrent.{MailBox, ops}

  class OnePlaceBuffer {
    private val m = new MailBox() {}          // An internal mailbox
    private case class Empty()                // Types of messages we deal with
    private case class Full(x: Int)

    m send Empty()                            // Initialization

    def write(x: Int) {
      m receive {
        case Empty() =>
          println("put " + x)
          m send Full(x)
      }
    }

    def read: Int = m receive {
      case Full(x) =>
        println("get " + x)
        m send Empty(); x
    }
  }

  def kill(delay: Int) = new java.util.Timer().schedule(
    new java.util.TimerTask {
      override def run() = {
        println("[killed]")
        exit(0)
      }
    },
    delay) // in milliseconds

  def main(args: Array[String]) {
    val buf = new OnePlaceBuffer
    val random = new java.util.Random()

    def producer(n: Int) {
      Thread.sleep(random.nextInt(1000))
      buf.write(n)
      producer(n + 1)
    }

    def consumer {
      Thread.sleep(random.nextInt(1000))
      val n = buf.read
      consumer
    }

    ops.spawn(producer(0))
    ops.spawn(consumer)
    kill(10000)
  }

}