Refactor code for clarity: standardize optional checks, improve list handling, and adjust PhantomPreSpawnEvent import.

api/src/main/java/com/alttd/boosterapi/data/BoosterCache.java

@@ -43,21 +43,23 @@ public class BoosterCache {
         LinkedList<Booster> list = boosters.get(boosterType);
         Booster oldActive = null;
         if (list.size() > 1) {
-            oldActive = list.get(0);
+            oldActive = list.getFirst();
         }
         list.sort(Booster::compareTo);
-        if (oldActive != null && !list.get(0).getBoosterUUID().equals(oldActive.getBoosterUUID())) {
+        if (oldActive != null && !list.getFirst().getBoosterUUID().equals(oldActive.getBoosterUUID())) {
             oldActive.updateDuration();
         }
     }
 
     public synchronized Optional<Booster> getActiveBooster(BoosterType boosterType) {
-        if (!boosters.containsKey(boosterType))
+        if (!boosters.containsKey(boosterType)) {
             return Optional.empty();
+        }
         LinkedList<Booster> list = boosters.get(boosterType);
-        if (list.isEmpty())
+        if (list.isEmpty()) {
             return Optional.empty();
-        return Optional.of(list.get(0));
+        }
+        return Optional.of(list.getFirst());
     }
 
     public synchronized List<Booster> getAllActiveBoosters() {

plugin/src/main/java/com/alttd/boosters/listeners/MyPetListener.java

@@ -25,8 +25,9 @@ public class MyPetListener implements Listener {
         }
 
         Optional<Booster> myPetBooster = boosterCache.getActiveBooster(BoosterType.MYPET);
-        if (myPetBooster.isEmpty())
+        if (myPetBooster.isEmpty()) {
             return;
+        }
 
         Booster booster = myPetBooster.get();
         event.setExp(booster.useMultiplier(event.getExp()));

plugin/src/main/java/com/alttd/boosters/listeners/PhantomSpawnListener.java

@@ -2,6 +2,7 @@ package com.alttd.boosters.listeners;
 
 import com.alttd.boosterapi.data.BoosterCache;
 import com.alttd.boosterapi.data.BoosterType;
+import com.destroystokyo.paper.event.entity.PhantomPreSpawnEvent;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
@@ -16,7 +17,7 @@ public class PhantomSpawnListener implements Listener {
     }
 
     @EventHandler
-    public void onPhantomPreSpawn(com.destroystokyo.paper.event.entity.PhantomPreSpawnEvent event) {
+    public void onPhantomPreSpawn(PhantomPreSpawnEvent event) {
         Entity spawningEntity = event.getSpawningEntity();
         if (spawningEntity instanceof Player
                 && boosterCache.getActiveBooster(BoosterType.PHANTOM).isPresent()) {

plugin/src/main/java/com/alttd/boosters/listeners/mcMMOListener.java

@@ -23,8 +23,9 @@ public class mcMMOListener implements Listener {
         String skillName = event.getSkill().name();
         BoosterType type = BoosterType.getByName(skillName);
         Optional<Booster> optionalBooster = boosterCache.getActiveBooster(type);
-        if (optionalBooster.isEmpty())
+        if (optionalBooster.isEmpty()) {
             return;
+        }
 
         Booster booster = optionalBooster.get();
         event.setRawXpGained(Math.round(booster.useMultiplier(event.getRawXpGained())));