- checkState((randomId && (id == null)) || (!randomId && (id != null)), "exactly one of random ID or custom ID must be set");
- checkState(sone != null, "sone must not be null");
- checkState((createdNow && (creationTime == 0)) || (!createdNow && (creationTime > 0)), "exactly one of created now or creation time must be set");