if (_tag2SubscriptionMap.containsKey(tag))
{
throw new AMQException("Consumer already exists with same tag: " + tag);
}
Subscription subscription =
SubscriptionFactoryImpl.INSTANCE.createSubscription(_channelId, _session, tag, acks, filters, noLocal, _creditManager);
// So to keep things straight we put before the call and catch all exceptions from the register and tidy up.
// We add before we register as the Async Delivery process may AutoClose the subscriber