refactor: we don't need explicit types here

src/main/java/emu/grasscutter/command/commands/SendMailCommand.java

@@ -25,7 +25,7 @@ public final class SendMailCommand implements CommandHandler {
 
     // Key = User that is constructing the mail.
     private static final HashMap<Integer, MailBuilder> mailBeingConstructed =
-            new HashMap<Integer, MailBuilder>();
+        new HashMap<>();
 
     // Yes this is awful and I hate it.
     @Override

src/main/java/emu/grasscutter/data/excels/EquipAffixData.java

@@ -46,7 +46,7 @@ public class EquipAffixData extends GameResource {
 
     @Override
     public void onLoad() {
-        ArrayList<FightPropData> parsed = new ArrayList<FightPropData>(getAddProps().length);
+        ArrayList<FightPropData> parsed = new ArrayList<>(getAddProps().length);
         for (FightPropData prop : getAddProps()) {
             if (prop.getPropType() != null && prop.getValue() != 0f) {
                 prop.onLoad();

src/main/java/emu/grasscutter/data/excels/avatar/AvatarTalentData.java

@@ -56,7 +56,7 @@ public class AvatarTalentData extends GameResource {
 
     @Override
     public void onLoad() {
-        ArrayList<FightPropData> parsed = new ArrayList<FightPropData>(getAddProps().length);
+        ArrayList<FightPropData> parsed = new ArrayList<>(getAddProps().length);
         for (FightPropData prop : getAddProps()) {
             if (prop.getPropType() != null || prop.getValue() == 0f) {
                 prop.onLoad();

src/main/java/emu/grasscutter/game/friends/FriendsList.java

@@ -15,8 +15,8 @@ public class FriendsList extends BasePlayerManager {
 
     public FriendsList(Player player) {
         super(player);
-        this.friends = new Int2ObjectOpenHashMap<Friendship>();
-        this.pendingFriends = new Int2ObjectOpenHashMap<Friendship>();
+        this.friends = new Int2ObjectOpenHashMap<>();
+        this.pendingFriends = new Int2ObjectOpenHashMap<>();
     }
 
     public boolean hasLoaded() {

src/main/java/emu/grasscutter/game/inventory/EquipInventoryTab.java

@@ -7,7 +7,7 @@ public class EquipInventoryTab implements InventoryTab {
     private final int maxCapacity;
 
     public EquipInventoryTab(int maxCapacity) {
-        this.items = new HashSet<GameItem>();
+        this.items = new HashSet<>();
         this.maxCapacity = maxCapacity;
     }
 

src/main/java/emu/grasscutter/game/mail/Mail.java

@@ -30,7 +30,7 @@ public final class Mail {
     public Mail() {
         this(
                 new MailContent(),
-                new ArrayList<MailItem>(),
+            new ArrayList<>(),
                 (int) Instant.now().getEpochSecond()
                         + 604800); // TODO: add expire time to send mail command
     }

src/main/java/emu/grasscutter/game/player/Player.java

@@ -1204,7 +1204,7 @@ public class Player implements PlayerHook, FieldFetch {
 
     public Map<String, MapMark> getMapMarks() {
         if (this.mapMarks == null) {
-            this.mapMarks = new HashMap<String, MapMark>();
+            this.mapMarks = new HashMap<>();
         }
         return mapMarks;
     }

src/main/java/emu/grasscutter/game/systems/InventorySystem.java

@@ -122,7 +122,7 @@ public class InventorySystem extends BaseGameSystem {
         int moraCost = 0;
         int expGain = 0;
 
-        List<GameItem> foodRelics = new ArrayList<GameItem>();
+        List<GameItem> foodRelics = new ArrayList<>();
         for (long guid : foodRelicList) {
             // Add to delete queue
             GameItem food = player.getInventory().getItemByGuid(guid);
@@ -139,7 +139,7 @@ public class InventorySystem extends BaseGameSystem {
             }
             foodRelics.add(food);
         }
-        List<ItemParamData> payList = new ArrayList<ItemParamData>();
+        List<ItemParamData> payList = new ArrayList<>();
         for (ItemParam itemParam : list) {
             int amount =
                     itemParam
@@ -347,7 +347,7 @@ public class InventorySystem extends BaseGameSystem {
 
         // Get exp gain
         int expGain = 0, expGainFree = 0;
-        List<GameItem> foodWeapons = new ArrayList<GameItem>();
+        List<GameItem> foodWeapons = new ArrayList<>();
         for (long guid : foodWeaponGuidList) {
             GameItem food = player.getInventory().getItemByGuid(guid);
             if (food == null || !food.isDestroyable()) {
@@ -359,7 +359,7 @@ public class InventorySystem extends BaseGameSystem {
             }
             foodWeapons.add(food);
         }
-        List<ItemParamData> payList = new ArrayList<ItemParamData>();
+        List<ItemParamData> payList = new ArrayList<>();
         for (ItemParam param : itemParamList) {
             int amount =
                     param.getCount(); // Previously this capped to inventory amount, but rejecting the payment

src/main/java/emu/grasscutter/game/world/Scene.java

@@ -396,10 +396,10 @@ public class Scene {
     }
 
     private static <T> List<List<T>> chopped(List<T> list, final int L) {
-        List<List<T>> parts = new ArrayList<List<T>>();
+        List<List<T>> parts = new ArrayList<>();
         final int N = list.size();
         for (int i = 0; i < N; i += L) {
-            parts.add(new ArrayList<T>(list.subList(i, Math.min(N, i + L))));
+            parts.add(new ArrayList<>(list.subList(i, Math.min(N, i + L))));
         }
         return parts;
     }

src/main/java/emu/grasscutter/scripts/SceneScriptManager.java

@@ -270,7 +270,7 @@ public class SceneScriptManager {
         // If that trigger has been refreshed, ensure it does not get
         // deregistered anyway when the trigger completes its invocation.
         for (var triggerSet : currentTriggers.values()) {
-            var toSave = new HashSet<SceneTrigger>(triggerSet);
+            var toSave = new HashSet<>(triggerSet);
             toSave.retainAll(ongoingTriggers);
             toSave.forEach(t -> t.setPreserved(true));
         }

src/main/java/emu/grasscutter/server/packet/recv/HandlerBuyGoodsReq.java

@@ -49,7 +49,7 @@ public class HandlerBuyGoodsReq extends PacketHandler {
             }
 
             List<ItemParamData> costs =
-                    new ArrayList<ItemParamData>(sg.getCostItemList()); // Can this even be null?
+                new ArrayList<>(sg.getCostItemList()); // Can this even be null?
             costs.add(new ItemParamData(202, sg.getScoin()));
             costs.add(new ItemParamData(201, sg.getHcoin()));
             costs.add(new ItemParamData(203, sg.getMcoin()));

src/main/java/emu/grasscutter/server/packet/send/PacketMailChangeNotify.java

@@ -15,11 +15,11 @@ public class PacketMailChangeNotify extends BasePacket {
     public PacketMailChangeNotify(Player player, Mail message) {
         this(
                 player,
-                new ArrayList<Mail>() {
-                    {
-                        add(message);
-                    }
-                });
+            new ArrayList<>() {
+                {
+                    add(message);
+                }
+            });
     }
 
     public PacketMailChangeNotify(Player player, List<Mail> mailList) {

src/main/java/emu/grasscutter/utils/lang/Language.java

@@ -261,22 +261,22 @@ public final class Language {
                         .collect(Collectors.toList());
 
         Map<TextStrings, TextStrings> canonicalTextStrings = new HashMap<>();
-        return new Int2ObjectOpenHashMap<TextStrings>(
-                nameHashes
-                        .intStream()
-                        .boxed()
-                        .collect(
-                                Collectors.toMap(
-                                        key -> key,
-                                        key -> {
-                                            TextStrings t =
-                                                    new TextStrings(
-                                                            IntStream.range(0, TextStrings.NUM_LANGUAGES)
-                                                                    .mapToObj(i -> languageMaps.get(i).get((int) key))
-                                                                    .collect(Collectors.toList()),
-                                                            key);
-                                            return canonicalTextStrings.computeIfAbsent(t, x -> t);
-                                        })));
+        return new Int2ObjectOpenHashMap<>(
+            nameHashes
+                .intStream()
+                .boxed()
+                .collect(
+                    Collectors.toMap(
+                        key -> key,
+                        key -> {
+                            TextStrings t =
+                                new TextStrings(
+                                    IntStream.range(0, TextStrings.NUM_LANGUAGES)
+                                        .mapToObj(i -> languageMaps.get(i).get((int) key))
+                                        .collect(Collectors.toList()),
+                                    key);
+                            return canonicalTextStrings.computeIfAbsent(t, x -> t);
+                        })));
     }
 
     @SuppressWarnings("unchecked")

src/main/java/emu/grasscutter/utils/objects/WeightedList.java

@@ -4,7 +4,7 @@ import java.util.*;
 import java.util.concurrent.ThreadLocalRandom;
 
 public class WeightedList<E> {
-    private final NavigableMap<Double, E> map = new TreeMap<Double, E>();
+    private final NavigableMap<Double, E> map = new TreeMap<>();
     private double total = 0;
 
     public WeightedList() {}