import scala.io._
import scala.actors._
import Actor._

object PageLoader {
  def getPageSize(url:String) = Source.fromURL(url, "ISO-8859-1").mkString.length
}

val urls = List("http://amazon.com",
                "http://twitter.com",
                "http://google.com",
                "http://cnn.com")

def timeMethod(method: () => Unit) = {
  val start = System.nanoTime
  method()
  val end = System.nanoTime
  println("Method took " + (end-start)/1000000000.0 + " seconds.")
}

def getPageSizeSequentially() = {
  for (url <- urls) {
    println("Size for " + url + ": " + PageLoader.getPageSize(url))
  }
}

def getPageSizeConcurrently() = {
  val caller = self

  for (url <- urls) {
    actor { caller ! (url, PageLoader.getPageSize(url)) }
  }

  for (i <- 1 to urls.size) {
    receive {
      case (url, size) =>
      println("Size for " + url + ": " + size)
    }
  }
}

println("Sequential run:")
timeMethod { getPageSizeSequentially }
println("Concurrent run:")
timeMethod { getPageSizeConcurrently }