ParserJava.kt

fun execute(url: String) {
  Executors.newSingleThreadExecutor().submit{
      val service = Executors.newFixedThreadPool(2)
      val f1 = service.submit<String>(XMLFetcher(url))
      try {
          val rssFeed = f1.get()
          val f2 = service.submit(XMLParser(rssFeed))
          onComplete.onTaskCompleted(f2.get())
      } catch (e: Exception) {
          onComplete.onError(e)
      } finally {
          service.shutdown()
      }
  }
}