Awaitility

A sort of Awaitility - Waiting until get an object from Supplier (java 8) with an interval and a timeout

    @SuppressWarnings("unchecked")
    private <T> T awaitUntil(long timeoutMillis, Supplier<T> supplier, long intervalMillis) throws InterruptedException {
        final Class<T> clazz = (Class<T>) ((ParameterizedType) supplier.getClass().getGenericSuperclass()).getActualTypeArguments()[0];
        final T[] arr = (T[]) Array.newInstance(clazz, 1);
        final boolean[] timeouts = new boolean[1];
        final ExecutorService executorService = Executors.newSingleThreadExecutor();
        executorService.execute(() -> {
            arr[0] = supplier.get();
            while (arr[0] == null && !timeouts[0]) {
                try {
                    Thread.sleep(intervalMillis);
                } catch (InterruptedException e) {
                    //
                }
                arr[0] = supplier.get();
            }
        });
        executorService.shutdown();
        executorService.awaitTermination(timeoutMillis, TimeUnit.MILLISECONDS);
        timeouts[0] = true;
        return arr[0];
    }