Okay, first of all, I know this may sound completely stupid. There is most likely some simple Java trick that I am missing with this and I just can't figure it out. I'm posting here because this is just driving me crazy. Anyways, so the title pretty much says it all. I'm created a plugin and I am working on a quest system in it currently. I'm trying to give the player 3 unique quests (So no duplicates). I can get the random number just fine, it's just that I am struggling with the unique part. I've tried some things like adding the number to a list and checking if it creates a duplicate, and then creating a new one if it is. The problem with this is I don't have an efficient way to recheck this new number after I create it (On the off chance that it creates another duplicate) Can someone help me?