We need to add blocking methods to CompletionStage!

[Kasper Nielsen]

>
> Would not mind a CancellableCompletionStage interface
> CancellableCompletionStage extends CompletionStage {
>   isCancelled();
>   cancel(boolean)
> }
>
>
Just wanted to note. This is not just a question about functionality. It is
also a signal to users
about "hey this a computation you can cancel". For example, if you where to
retrofit all of
java.nio you would probably use CancellableCompletionStage (or whatever the
name)
for all methods. You do not really need to set an int or whatever the
read/write methods return
in 99% of all cases.

Best
  Kasper