FailSafe

Dynamic and concurrent retry constructs for the JVM.

public static void main(String[] args) {
    final Suspensor suspensor = Suspensor.blocking().intercept(millis -> System.out.println("Sleeping for: " + Duration.ofMillis(millis)));
    final EasingFunction delay = fixed(100).plus(linear(150)).plus(random(50, 250)).limit(5000);

    final AtomicInteger count = new AtomicInteger(0);
    final Consumer<Throwable> logger = (e) -> System.out.println("[" + Instant.now() + " - " + count.incrementAndGet() + "] Received: " + e);
    final RetryCondition<Throwable> log = RetryCondition.intercept(logger);
    final RetryCondition<Throwable> backoff = RetryCondition.backoff(delay, suspensor);

    final RetryCondition<Throwable> rejection = log.and(backoff);

    final CallableTask<?> task = () -> {
        Thread.sleep(500); // simulate expensive task
        if (ThreadLocalRandom.current().nextBoolean()) {
            throw new IllegalStateException("Not OK"); // ... that may fail
        }
        return "OK";
    };

    final ExecutionResult<?, ?> execution;
    if (ThreadLocalRandom.current().nextBoolean()) {
        execution = Retry.defer(task, rejection); // asynchronous (non-blocking)
    } else {
        execution = Retry.sync(task, rejection); // synchronous (blocking)
    }

    if (ThreadLocalRandom.current().nextBoolean()) { // attempt to cancel the execution of the task
        execution.cancel(true);
    }

    System.out.println("Handle ==> " + execution);
    System.out.println("Result ==> " + execution.unwrap());
}