Uses of Interface
org.bukkit.advancement.Advancement

Packages that use Advancement 
Package Description
org.bukkit
The root package of the Bukkit API, contains generalized API classes.
org.bukkit.advancement
Classes relevant to advancements.
org.bukkit.entity
Interfaces for non-voxel objects that can exist in a world, including all players, monsters, projectiles, etc.
org.bukkit.event.player
Events relating to players.