public void writeRating(Rating rating) throws IOException {
// the buffer should already be clear
assert ratingBuffer.position() == 0;
assert ratingBuffer.limit() == ratingBuffer.capacity();
checkUpgrade(rating.getUserId(), rating.getItemId());
// and use it
format.renderRating(rating, ratingBuffer);
ratingBuffer.flip();
BinaryUtils.writeBuffer(channel, ratingBuffer);
ratingBuffer.clear();
saveIndex(userMap, rating.getUserId(), index);
saveIndex(itemMap, rating.getItemId(), index);
index += 1;
if (format.hasTimestamps()) {
long ts = rating.getTimestamp();
// did this timestamp send us backwards?
if (ts < lastTimestamp && !needsSorting) {
logger.debug("found out-of-order timestamps, activating sorting");
needsSorting = true;
}
lastTimestamp = ts;
}
}
