Object attribute = Channels.getAttribute(channel);
LOGGER.debug("Channel Closed: {} with attribute {}", channel, attribute);
if (attribute instanceof Callback) {
Callback callback = (Callback) attribute;
Channels.setAttribute(channel, callback.future());
callback.call();
} else if (attribute instanceof NettyResponseFuture<?>) {
NettyResponseFuture<?> future = NettyResponseFuture.class.cast(attribute);
future.touch();