YAML configuration hierarchy

You will notice the hierarchy when working with ItemStack in YAML. This is similar to how commands and permissions have nested values in our plugin.yml files. We can utilize a hierarchy within our config file to make it easier to use and understand.

We want to give items to two types of mobs; zombies and skeletons. Each type will have unique armor and a unique weapon. This means that we will need ten different ItemStack classes. We could name them ZombieHolding, SkeletonHolding, ZombieHelmet, SkeletonHelmet, and so on. However, a hierarchy would be much more efficient. We will have a Zombie key and a Skeleton key. Within each of them we will have a key for each item. The following is a sample of the hierarchy of the mob armor segment of the config file:

Zombie:
  holding:
    ==: org.bukkit.inventory.ItemStack
    type: STONE_SWORD
  helmet:
    ==: org.bukkit.inventory.ItemStack
    type: CHAINMAIL_HELMET

Skeleton:
  holding:
    ==: org.bukkit.inventory.ItemStack...