Add more stuff to api

common/src/main/java/me/lucko/luckperms/utils/AbstractListener.java

@@ -35,14 +35,6 @@ public class AbstractListener {
         }
     }
 
-    protected void onLogin(UUID uuid, String username) {
-
-    }
-
-    protected void onJoin(UUID uuid, String username) {
-
-    }
-
     protected void onLeave(UUID uuid) {
         final UuidCache cache = plugin.getUuidCache();
 

common/src/main/java/me/lucko/luckperms/utils/UuidCache.java

@@ -7,6 +7,15 @@ import java.util.Optional;
 import java.util.UUID;
 import java.util.concurrent.ConcurrentHashMap;
 
+/**
+ * This UuidCache is a means of allowing users to have the same internal UUID across a network of offline mode servers
+ * or mixed offline mode and online mode servers. Platforms running in offline mode generate a random UUID for a user when
+ * they first join the server, but this UUID will then not be consistent across the network. LuckPerms will instead check
+ * the datastore cache, to get a UUID for a user that is consistent across an entire network.
+ *
+ * If you want to get a user object from the datastore using the api on a server in offline mode, you will need to use this cache,
+ * OR use Datastore#getUUID, for users that are not online.
+ */
 public class UuidCache {
 
     // External UUID --> Internal UUID