Getting all keys from a specific path only?

I save my data in this format:

Code:

Arenas:
  Worlds:
    world:
      Name:
        test2:
          Locations:
            l1:
              X: 50
              Y: 68
              Z: 203
            l2:
              X: 51
              Y: 68
              Z: 202
        test1:
          Locations:
            l1:
              X: 46
              Y: 68
              Z: 206
            l2:
              X: 47
              Y: 68
              Z: 205

And i'm trying to get all, e.g worlds that are made (in this case one, "world").

so i want to get all keys after "Arenas.Worlds" but not after the next key.

so i don't want "Arenas.Worlds.world.Name.test1.Locations.ECT".
all i want as an answer is "Arenas.Worlds.world".

so far all i found was:

Code:

Set<String> a = GGCPlugin.GameSettings.getKeys(true);

This gets all paths possible, e.g:

Code:

Arenas
Arenas.Worlds
Arenas.Worlds.world
Arenas.Worlds.world.Name
Arenas.Worlds.world.Name.test1
Arenas.Worlds.world.Name.test1.Locations

 

Code:

config.getConfigurationSection("Arenas.Worlds").getKeys(false))

 

thanks