If you use Multiverse Adventure, you can easily reset automatically a world after everyone has left it.
Works great in 1.8

Then it should not get named read-only. A better option would be to disable player data saving of players in that world

I will test that, but it would still be a neat addtion to the API and also much easier.

I think there is a anything like a WorldLoadEvent. When you configure that your plugin loads before world loading, you can catch this event and disable saving there.

Also you cant do that on the default world (dim 0)

Jan, I know that, but the point is, that the server will still save playerdata and such, I dont want that.

I use disabling world saving by plugins for more than 1 year now, and there have never been any problem. Just unload the world without saving after your game and load it again. After loading your world use world.setAutoSave(false);

https://hub.spigotmc.org/javadocs/bukkit/org/bukkit/World.html#setAutoSave(boolean)
https://hub.spigotmc.org/javadocs/bukkit/org/bukkit/Server.html#unloadWorld(org.bukkit.World,%20boolean)

You can not disable saving with plugins, I have done a lot of testing about this.

Unneeded. Just set world saving to false (can also be done by plugins!) and restart the server.

This would be very helpful indeed as it would be a much more memory and processor efficient method of resetting the world once the adventure map or minigame is completed and changes were made that need to be reverted for the map to be functional once again. I have had many times where world reset plugins have crashed the server and once even the computer. I have tried many different plugins, but none will work properly so this would be a big help as you could then do some sort of special restart/stop command (or if world saving is disabled in the config) just restart/stop the server and nothing is saved, but the server kicks players and shuts down like normal.