[1.8] World's UUID?

[Ernio]

What is the most persistent/unique data about world?

 

E.g if I would have world with name X, then remove it, create new onw with same name X, and even same seed. Can I tell if that world is different (like, literally UUID, which I can't find, or probably will in next minutes)?

[Draco18s]

I don't think worlds (saves) have UUIDs.

 

Why?

[TrashCaster]

What you could do, if it's something you want to implement, just check the System.currentMillis upon making a world, and use that in NBT of the world save (if that's possible), or in some kind of world-save file. That should provide enough "uniqueness" that you can identify a world with. But there is no UUID for worlds.

[Ernio]

Well, I don't see anything that stops me from making my own world UUID. (WorldSaveData)

 

Thanks for reassuring that those don't exist in vanilla.

[TrashCaster]

They are called Dimension ID

 

I believe OP was referring to each world having a unique identifier (same ID for all dimensions), so if someone deleted their world, re-creating one with the same generation settings would still result in a different world, since they'd have a unique identifier generated upon creation.

[jabelar]

I think there must be something unique about the save games though, because if you create two worlds with same name and same seed they both still show up in the load world list as separate worlds. I would look at how the load game menu works as it must iterate through some list with unique entries.