SenderWithCallBacks.java

        final List<String> tokens = Arrays.asList(
                "123",
                "456"
        );

        final ApnsClient apnsClient;
        {
            try {
                apnsClient =new ApnsClientBuilder()
                            .setClientCredentials(new File("/home/Matthias/jajajaj.p12"), "jaja ja")
                            .build();
            } catch (Exception e) {
                e.printStackTrace();
                return;
            }
        }

        final Future<Void> connectFuture = apnsClient.connect(ApnsClient.DEVELOPMENT_APNS_HOST);
        connectFuture.addListener(new GenericFutureListener<Future<? super Void>>() {
            @Override
            public void operationComplete(Future<? super Void> future) throws Exception {

                if (future.isSuccess() && apnsClient.isConnected()) {

                    LOGGER.info("Sending stuff");


                    for (final String token: tokens) {

                        final SimpleApnsPushNotification pushNotification = createNotification(token, "Here is iteration: " + token);
                        final Future<PushNotificationResponse<SimpleApnsPushNotification>> sendNotificationFuture = apnsClient.sendNotification(pushNotification);

                        sendNotificationFuture.addListener(new GenericFutureListener<Future<? super PushNotificationResponse<SimpleApnsPushNotification>>>() {
                            @Override
                            public void operationComplete(Future<? super PushNotificationResponse<SimpleApnsPushNotification>> pushNotificationFutue) throws Exception {
                                if (pushNotificationFutue.isSuccess()) {
                                    final PushNotificationResponse<SimpleApnsPushNotification> pushNotificationResponse =
                                            sendNotificationFuture.get();

                                    if (pushNotificationResponse.isAccepted()) {
                                        LOGGER.info("Push notification accepted by APNs gateway." + pushNotificationResponse);
                                    } else {
                                        LOGGER.info("NOPE: " + pushNotificationResponse);
                                    }
                                }
                            }
                        });
                    }

                    LOGGER.warning("here we go....");
                    final Future<Void> disconnectFuture = apnsClient.disconnect();

                    disconnectFuture.addListener(new GenericFutureListener<Future<? super Void>>() {
                        @Override
                        public void operationComplete(Future<? super Void> future) throws Exception {

                            if(future.isSuccess()) {
                                LOGGER.info("AM I connected ? " + apnsClient.isConnected());
                            }
                        }
                    });
                }
            }
        });

        LOGGER.info("moving on, while the sending happens...");