while (!task.isDone()) {
      Thread.sleep(500);
      switch(task.getState()) {
        case RUNNING: System.out.print("R."); break;
        case ABORTED": System.out.println(" ... aborted."); break;
        case READY: System.out.println(" ... ready."); break;
        default: System.out.println("uknown state");
      }

    }