ScheduledExecutorService Exception handling

Question

I use ScheduledExecutorService to execute a method periodically.

p-code:

ScheduledExecutorService scheduler = Executors.newSingleThreadScheduledExecu         


        

Answer 1

I know that this is old question, but if somebody is using delayed CompletableFuture with ScheduledExecutorService then should handle this in that way:

private static CompletableFuture delayed(Duration delay) {
    CompletableFuture delayed = new CompletableFuture<>();
    executor.schedule(() -> {
        String value = null;
        try {
            value = mayThrowExceptionOrValue();
        } catch (Throwable ex) {
            delayed.completeExceptionally(ex);
        }
        if (!delayed.isCompletedExceptionally()) {
            delayed.complete(value);
        }
    }, delay.toMillis(), TimeUnit.MILLISECONDS);
    return delayed;
}

and handling exception in CompletableFuture:

CompletableFuture delayed = delayed(Duration.ofSeconds(5));
delayed.exceptionally(ex -> {
    //handle exception
    return null;
}).thenAccept(value -> {
    //handle value
});