How to check Scanner.hasNext(System.in) with a timeout if nothing is typed?

Question

Scanner sc = new Scanner(System.in);

Scanner can be used for reading text files, user input streams, and more. I am specifically using it for readi

Answer 1

I see nothing wrong with having a Producer - Consumer here:

// Shared queue
final Queue<String> messages = new ConcurrentLinkedQueue<>();

// Non-blocking consumer
ScheduledExecutorService ses = Executors.newSingleThreadScheduledExecutor();
ses.scheduleAtFixedRate(new Runnable(){
    @Override
    public void run() {
        // non-blocking
        while((String message = messages.poll()) != null) {
            // do something
        }
    }
}, 0, 10, TimeUnit.MILLISECONDS);

// Blocking producer
Scanner sc = new Scanner(System.in);
while(sc.hasNext()) {
    messages.add(sc.next());
}

The consumer can then just do non-blocking on the shared Queue. Only the producer knows that it is filled as soon as a new message is read.