/**
* Return a random GlobalAttributeValueId
*
* @return
*/
public GlobalAttributeValueId getRandomGlobalAttributeValue() {
int offset = rng.nextInt(this.gag_ids.size());
GlobalAttributeGroupId gag_id = this.gag_ids.get(offset);
assert (gag_id != null);
int count = rng.nextInt(gag_id.getCount());
GlobalAttributeValueId gav_id = new GlobalAttributeValueId(gag_id, count);
return gav_id;
}
public ItemInfo getRandomItem() {
assert (this.getAllItemsCount() > 0);
int idx = -1;
while (idx == -1 || allItemSets[idx].isEmpty()) {
idx = rng.nextInt(allItemSets.length);
} // WHILE
return (this.getRandomItem(allItemSets[idx], false, false));
}
/**
* Note that this synchronization block only matters for the loader
*
* @param min_item_count
* @param clientId - Will use null if less than zero
* @param exclude
* @return
*/
private synchronized UserId getRandomUserId(int min_item_count, int clientId, UserId... exclude) {
// We use the UserIdGenerator to ensure that we always select the next UserId for
// a given client from the same set of UserIds
if (this.randomItemCount == null) {
this.randomItemCount = new FlatHistogram<Long>(this.rng, this.users_per_itemCount);
}
if (this.userIdGenerator == null) this.initializeUserIdGenerator(clientId);
UserId user_id = null;
int tries = 1000;
final long num_users = this.userIdGenerator.getTotalUsers() - 1;
while (user_id == null && tries-- > 0) {
// We first need to figure out how many items our seller needs to have
long itemCount = -1;
// assert(min_item_count < this.users_per_item_count.getMaxValue());
while (itemCount < min_item_count) {
itemCount = this.randomItemCount.nextValue();
} // WHILE
// Set the current item count and then choose a random position
// between where the generator is currently at and where it ends
this.userIdGenerator.setCurrentItemCount((int) itemCount);
long cur_position = this.userIdGenerator.getCurrentPosition();
long new_position = rng.number(cur_position, num_users);
user_id = this.userIdGenerator.seekToPosition((int) new_position);
if (user_id == null) continue;
// Make sure that we didn't select the same UserId as the one we were
// told to exclude.
if (exclude != null && exclude.length > 0) {
for (UserId ex : exclude) {
if (ex != null && ex.equals(user_id)) {
if (LOG.isTraceEnabled()) LOG.trace("Excluding " + user_id);
user_id = null;
break;
}
} // FOR
if (user_id == null) continue;
}
// If we don't care about skew, then we're done right here
if (LOG.isTraceEnabled()) LOG.trace("Selected " + user_id);
break;
} // WHILE
if (user_id == null && LOG.isDebugEnabled()) {
LOG.warn(
String.format(
"Failed to select a random UserId "
+ "[minItemCount=%d, clientId=%d, exclude=%s, totalPossible=%d, currentPosition=%d]",
min_item_count,
clientId,
Arrays.toString(exclude),
this.userIdGenerator.getTotalUsers(),
this.userIdGenerator.getCurrentPosition()));
}
return (user_id);
}
