- boolean hasFriend(String friendSoneId);
-
- /**
- * Adds the given Sone as a friend Sone.
- *
- * @param friendSone
- * The friend Sone to add
- * @return This Sone (for method chaining)
- */
- Sone addFriend(String friendSone);
-
- /**
- * Removes the given Sone as a friend Sone.
- *
- * @param friendSoneId
- * The ID of the friend Sone to remove
- * @return This Sone (for method chaining)
- */
- Sone removeFriend(String friendSoneId);