private final Function2<String, Float, Tuple0> beginTask;
private final Function1<Tuple0, Tuple0> done;
private final Function1<Tuple0, Boolean> isCanceled;
private final Function2<String, Float, Tuple0> beginTask;
private final Function1<Tuple0, Tuple0> done;
private final Function1<Tuple0, Boolean> isCanceled;