<dependency>
    <groupId>com.turo</groupId>
    <artifactId>pushy</artifactId>
    <version>0.11.1</version>
</dependency>

ApnsClient apnsClient = new ApnsClientBuilder()
    .setClientCredentials(new File("/path/to/certificate.p12"), "p12-file-password")
    .build();

ApnsClient apnsClient = new ApnsClientBuilder().setApnsServer(ApnsClientBuilder.DEVELOPMENT_APNS_HOST)
    .setClientCredentials(new File("/path/to/certificate.p12"), "p12-file-password")
    .build();

EventLoopGroup eventLoopGroup = new NioEventLoopGroup(4);
ApnsClient apnsClient = new ApnsClientBuilder()
        .setClientCredentials(new File("/path/to/certificate.p12"), "p12-file-password")
        .setConcurrentConnections(4).setEventLoopGroup(eventLoopGroup).build();

for (final ApnsPushNotification pushNotification : collectionOfPushNotifications) {
    final Future sendNotificationFuture = apnsClient.sendNotification(pushNotification);

    sendNotificationFuture.addListener(new GenericFutureListener<Future<PushNotificationResponse>>() {
        
        @Override
        public void operationComplete(final Future<PushNotificationResponse> future) throws Exception {
            // This will get called when the sever has replied and returns immediately
            final PushNotificationResponse response = future.getNow();
        }
    });
}

public class IOSPush {

    private static final Logger logger = LoggerFactory.getLogger(IOSPush.class);

    private static final ApnsClient apnsClient = null;

    private static final Semaphore semaphore = new Semaphore(10000);

    public void push(final List<String> deviceTokens, String alertTitle, String alertBody) {

        long startTime = System.currentTimeMillis();

        if (apnsClient == null) {
            try {
                EventLoopGroup eventLoopGroup = new NioEventLoopGroup(4);
                apnsClient = new ApnsClientBuilder().setApnsServer(ApnsClientBuilder.DEVELOPMENT_APNS_HOST)
                        .setClientCredentials(new File("/path/to/certificate.p12"), "p12-file-password")
                        .setConcurrentConnections(4).setEventLoopGroup(eventLoopGroup).build();
            } catch (Exception e) {
                logger.error("ios get pushy apns client failed!");
                e.printStackTrace();
            }
        }

        long total = deviceTokens.size();

        final CountDownLatch latch = new CountDownLatch(deviceTokens.size());

        final AtomicLong successCnt = new AtomicLong(0);

        long startPushTime =  System.currentTimeMillis();

        for (String deviceToken : deviceTokens) {
            ApnsPayloadBuilder payloadBuilder = new ApnsPayloadBuilder();
            payloadBuilder.setAlertBody(alertBody);
            payloadBuilder.setAlertTitle(alertTitle);
            
            String payload = payloadBuilder.buildWithDefaultMaximumLength();
            final String token = TokenUtil.sanitizeTokenString(deviceToken);
            SimpleApnsPushNotification pushNotification = new SimpleApnsPushNotification(token, "com.example.myApp", payload);

            try {
                semaphore.acquire();
            } catch (InterruptedException e) {
                logger.error("ios push get semaphore failed, deviceToken:{}", deviceToken);
                e.printStackTrace();
            }
            final Future<PushNotificationResponse<SimpleApnsPushNotification>> future = apnsClient.sendNotification(pushNotification);

            future.addListener(new GenericFutureListener<Future<PushNotificationResponse>>() {
                @Override
                public void operationComplete(Future<PushNotificationResponse> pushNotificationResponseFuture) throws Exception {
                    if (future.isSuccess()) {
                        final PushNotificationResponse<SimpleApnsPushNotification> response = future.getNow();
                        if (response.isAccepted()) {
                            successCnt.incrementAndGet();
                        } else {
                            Date invalidTime = response.getTokenInvalidationTimestamp();
                            logger.error("Notification rejected by the APNs gateway: " + response.getRejectionReason());
                            if (invalidTime != null) {
                                logger.error("\t…and the token is invalid as of " + response.getTokenInvalidationTimestamp());
                            }
                        }
                    } else {
                        logger.error("send notification device token={} is failed {} ", token, future.cause().getMessage());
                    }
                    latch.countDown();
                    semaphore.release();
                }
            });
        }

        try {
            latch.await(20, TimeUnit.SECONDS);
        } catch (InterruptedException e) {
            logger.error("ios push latch await failed!");
            e.printStackTrace();
        }

        long endPushTime = System.currentTimeMillis();

        logger.info("test pushMessage success. [共推送" + total + "个][成功" + (successCnt.get()) + "个], 
            totalcost= " + (endPushTime - startTime) + ", pushCost=" + (endPushTime - startPushTime));
    }
}