logger.log(Level.FINE, "Sending transformed APNs payload: " + apnsMessage);
// send:
service.start();
Date expireDate = createFutureDateBasedOnTTL(pushMessage.getTimeToLive());
service.push(tokens, apnsMessage, expireDate);
logger.log(Level.INFO, "Message to APNs has been submitted");
// after sending, let's ask for the inactive tokens:
final Set<String> inactiveTokens = service.getInactiveDevices().keySet();
// transform the tokens to be all lower-case: