General cleanup

src/main/java/net/minestom/server/advancements/AdvancementTab.java

@@ -35,7 +35,7 @@ public class AdvancementTab implements Viewable {
     protected ByteBuf createBuffer;
     // the packet used to clear the tab (used to remove it and to update an advancement)
     // will never change (since the root identifier is always the same)
-    protected ByteBuf removeBuffer;
+    protected final ByteBuf removeBuffer;
 
     protected AdvancementTab(String rootIdentifier, AdvancementRoot root) {
         this.root = root;

src/main/java/net/minestom/server/advancements/notifications/NotificationCenter.java

@@ -47,10 +47,8 @@ public class NotificationCenter {
      * @param players      the collection of players to send the notification to
      */
     public static void send(Notification notification, Collection<Player> players) {
-        // Can't use PacketWriterUtils before we need the packets to come in the correct order
+        // Can't use PacketWriterUtils because we need the packets to come in the correct order
-        players.forEach(player -> {
+        players.forEach(player -> send(notification, player));
-            send(notification, player);
-        });
     }
 
     /**

src/main/java/net/minestom/server/benchmark/BenchmarkManager.java

@@ -27,18 +27,18 @@ import static net.minestom.server.MinecraftServer.*;
  */
 public final class BenchmarkManager {
 
-    public static ThreadMXBean threadMXBean = ManagementFactory.getThreadMXBean();
+    public static final ThreadMXBean THREAD_MX_BEAN = ManagementFactory.getThreadMXBean();
-    private static List<String> threads = new ArrayList<>();
+    private static final List<String> THREADS = new ArrayList<>();
 
     static {
-        threadMXBean.setThreadContentionMonitoringEnabled(true);
+        THREAD_MX_BEAN.setThreadContentionMonitoringEnabled(true);
-        threadMXBean.setThreadCpuTimeEnabled(true);
+        THREAD_MX_BEAN.setThreadCpuTimeEnabled(true);
 
-        threads.add(THREAD_NAME_MAIN_UPDATE);
+        THREADS.add(THREAD_NAME_MAIN_UPDATE);
-        threads.add(THREAD_NAME_PACKET_WRITER);
+        THREADS.add(THREAD_NAME_PACKET_WRITER);
-        threads.add(THREAD_NAME_BLOCK_BATCH);
+        THREADS.add(THREAD_NAME_BLOCK_BATCH);
-        threads.add(THREAD_NAME_SCHEDULER);
+        THREADS.add(THREAD_NAME_SCHEDULER);
-        threads.add(THREAD_NAME_TICK);
+        THREADS.add(THREAD_NAME_TICK);
     }
 
     private final Long2LongMap lastCpuTimeMap = new Long2LongOpenHashMap();
@@ -85,7 +85,7 @@ public final class BenchmarkManager {
     }
 
     public void addThreadMonitor(String threadName) {
-        threads.add(threadName);
+        THREADS.add(threadName);
     }
 
     /**
@@ -119,11 +119,11 @@ public final class BenchmarkManager {
     }
 
     private void refreshData() {
-        ThreadInfo[] threadInfo = threadMXBean.getThreadInfo(threadMXBean.getAllThreadIds());
+        ThreadInfo[] threadInfo = THREAD_MX_BEAN.getThreadInfo(THREAD_MX_BEAN.getAllThreadIds());
         for (ThreadInfo threadInfo2 : threadInfo) {
             final String name = threadInfo2.getThreadName();
             boolean shouldBenchmark = false;
-            for (String thread : threads) {
+            for (String thread : THREADS) {
                 if (name.startsWith(thread)) {
                     shouldBenchmark = true;
                     break;
@@ -141,8 +141,8 @@ public final class BenchmarkManager {
 
             final long blockedTime = threadInfo2.getBlockedTime();
             final long waitedTime = threadInfo2.getWaitedTime();
-            final long cpuTime = threadMXBean.getThreadCpuTime(id);
+            final long cpuTime = THREAD_MX_BEAN.getThreadCpuTime(id);
-            final long userTime = threadMXBean.getThreadUserTime(id);
+            final long userTime = THREAD_MX_BEAN.getThreadUserTime(id);
 
             lastCpuTimeMap.put(id, cpuTime);
             lastUserTimeMap.put(id, userTime);

src/main/java/net/minestom/server/chat/RichMessage.java

@@ -21,7 +21,7 @@ import java.util.List;
  */
 public class RichMessage extends JsonMessage {
 
-    private List<RichComponent> components = new ArrayList<>();
+    private final List<RichComponent> components = new ArrayList<>();
     private RichComponent currentComponent;
 
     /**
@@ -214,8 +214,8 @@ public class RichMessage extends JsonMessage {
      */
     private static class RichComponent {
 
-        private ColoredText text;
+        private final ColoredText text;
-        private FormatRetention formatRetention;
+        private final FormatRetention formatRetention;
         private ChatClickEvent clickEvent;
         private ChatHoverEvent hoverEvent;
         private String insertion;

src/main/java/net/minestom/server/chat/TranslatableText.java

@@ -5,8 +5,8 @@ package net.minestom.server.chat;
  */
 public class TranslatableText {
 
-    private String code;
+    private final String code;
-    private String[] arguments;
+    private final String[] arguments;
 
     private TranslatableText(String code, String[] arguments) {
         this.code = code;

src/main/java/net/minestom/server/collision/BoundingBox.java

@@ -11,7 +11,7 @@ import net.minestom.server.utils.Vector;
 public class BoundingBox {
 
     private final Entity entity;
-    private float x, y, z;
+    private final float x, y, z;
 
     /**
      * Creates a {@link BoundingBox} linked to an {@link Entity} and with a specific size.

src/main/java/net/minestom/server/command/CommandManager.java

@@ -37,10 +37,10 @@ public final class CommandManager {
 
     private boolean running;
 
-    private ConsoleSender consoleSender = new ConsoleSender();
+    private final ConsoleSender consoleSender = new ConsoleSender();
 
-    private CommandDispatcher dispatcher = new CommandDispatcher();
+    private final CommandDispatcher dispatcher = new CommandDispatcher();
-    private Map<String, CommandProcessor> commandProcessorMap = new HashMap<>();
+    private final Map<String, CommandProcessor> commandProcessorMap = new HashMap<>();
 
     public CommandManager() {
         running = true;

src/main/java/net/minestom/server/entity/EntityCreature.java

@@ -36,8 +36,8 @@ public abstract class EntityCreature extends LivingEntity {
     private IPath path;
     private Position pathPosition;
 
-    protected List<GoalSelector> goalSelectors = new ArrayList<>();
+    protected final List<GoalSelector> goalSelectors = new ArrayList<>();
-    protected List<TargetSelector> targetSelectors = new ArrayList<>();
+    protected final List<TargetSelector> targetSelectors = new ArrayList<>();
     private GoalSelector currentGoalSelector;
 
     private Entity target;

src/main/java/net/minestom/server/entity/Player.java

@@ -74,7 +74,7 @@ public class Player extends LivingEntity implements CommandSender {
     private boolean answerKeepAlive;
 
     private String username;
-    protected PlayerConnection playerConnection;
+    protected final PlayerConnection playerConnection;
     protected final Set<Entity> viewableEntities = new CopyOnWriteArraySet<>();
 
     private int latency;
@@ -490,7 +490,7 @@ public class Player extends LivingEntity implements CommandSender {
 
     /**
      * Respawns the player by sending a {@link RespawnPacket} to the player and teleporting him
-     * to {@link #getRespawnPoint()}. It also resetso fire and his health
+     * to {@link #getRespawnPoint()}. It also resets fire and his health
      */
     public void respawn() {
         if (!isDead())
@@ -694,7 +694,7 @@ public class Player extends LivingEntity implements CommandSender {
      * Sends a legacy message with the specified color char.
      *
      * @param text      the text with the legacy color formatting
-     * @param colorChar the color charactero
+     * @param colorChar the color character
      */
     public void sendLegacyMessage(String text, char colorChar) {
         ColoredText coloredText = ColoredText.ofLegacy(text, colorChar);

src/main/java/net/minestom/server/entity/ai/GoalSelector.java

@@ -5,7 +5,7 @@ import net.minestom.server.entity.EntityCreature;
 
 public abstract class GoalSelector {
 
-    protected EntityCreature entityCreature;
+    protected final EntityCreature entityCreature;
 
     public GoalSelector(EntityCreature entityCreature) {
         this.entityCreature = entityCreature;

src/main/java/net/minestom/server/entity/ai/goal/DoNothingGoal.java

@@ -10,8 +10,8 @@ public class DoNothingGoal extends GoalSelector {
 
     private static final Random RANDOM = new Random();
 
-    private long time;
+    private final long time;
-    private float chance;
+    private final float chance;
     private long startTime;
 
     /**

src/main/java/net/minestom/server/entity/ai/goal/MeleeAttackGoal.java

@@ -9,14 +9,14 @@ import net.minestom.server.utils.time.CooldownUtils;
 import net.minestom.server.utils.time.TimeUnit;
 
 /**
- * Attack the entity's target ({@link EntityCreature#getTarget()}) OR the closest entity
+ * Attacks the entity's target ({@link EntityCreature#getTarget()}) OR the closest entity
- * which can be targeted with the entity {@link TargetSelector}
+ * which can be targeted with the entity {@link TargetSelector}.
  */
 public class MeleeAttackGoal extends GoalSelector {
 
     private long lastHit;
-    private int delay;
+    private final int delay;
-    private TimeUnit timeUnit;
+    private final TimeUnit timeUnit;
 
     private boolean stop;
 

src/main/java/net/minestom/server/entity/ai/goal/RandomStrollGoal.java

@@ -12,8 +12,8 @@ public class RandomStrollGoal extends GoalSelector {
 
     private static final long DELAY = 2500;
 
-    private int radius;
+    private final int radius;
-    private List<Position> closePositions;
+    private final List<Position> closePositions;
 
     private long lastStroll;
 

src/main/java/net/minestom/server/entity/ai/target/LastEntityDamagerTarget.java

@@ -7,11 +7,11 @@ import net.minestom.server.entity.damage.DamageType;
 import net.minestom.server.entity.damage.EntityDamage;
 
 /**
- * Target the last damager of this entity
+ * Targets the last damager of this entity.
  */
 public class LastEntityDamagerTarget extends TargetSelector {
 
-    private float range;
+    private final float range;
 
     public LastEntityDamagerTarget(EntityCreature entityCreature, float range) {
         super(entityCreature);

src/main/java/net/minestom/server/entity/fakeplayer/FakePlayer.java

@@ -12,8 +12,8 @@ import java.util.function.Consumer;
 
 public class FakePlayer extends Player {
 
-    private FakePlayerOption option;
+    private final FakePlayerOption option;
-    private FakePlayerController fakePlayerController;
+    private final FakePlayerController fakePlayerController;
 
     private FakePlayer(UUID uuid, String username, FakePlayerOption option) {
         super(uuid, username, new FakePlayerConnection());
@@ -40,9 +40,7 @@ public class FakePlayer extends Player {
     public static void initPlayer(UUID uuid, String username, FakePlayerOption option, Consumer<FakePlayer> scheduledCallback) {
         final FakePlayer fakePlayer = new FakePlayer(uuid, username, option);
 
-        fakePlayer.addEventCallback(PlayerLoginEvent.class, event -> {
+        fakePlayer.addEventCallback(PlayerLoginEvent.class, event -> MinecraftServer.getSchedulerManager().buildTask(() -> scheduledCallback.accept(fakePlayer)).delay(1, TimeUnit.TICK).schedule());
-            MinecraftServer.getSchedulerManager().buildTask(() -> scheduledCallback.accept(fakePlayer)).delay(1, TimeUnit.TICK).schedule();
-        });
     }
 
     /**

src/main/java/net/minestom/server/entity/fakeplayer/FakePlayerController.java

@@ -16,11 +16,11 @@ import net.minestom.server.utils.BlockPosition;
 import net.minestom.server.utils.inventory.PlayerInventoryUtils;
 
 /**
- * This class act as a client controller for {@link FakePlayer}
+ * This class act as a client controller for {@link FakePlayer}.
  */
 public class FakePlayerController {
 
-    private FakePlayer fakePlayer;
+    private final FakePlayer fakePlayer;
 
     public FakePlayerController(FakePlayer fakePlayer) {
         this.fakePlayer = fakePlayer;

src/main/java/net/minestom/server/entity/pathfinding/PFColumnarSpace.java

@@ -9,8 +9,8 @@ import net.minestom.server.instance.Chunk;
 public class PFColumnarSpace implements IColumnarSpace {
 
     private final ColumnarOcclusionFieldList occlusionFieldList = new ColumnarOcclusionFieldList(this);
-    private PFInstanceSpace instanceSpace;
+    private final PFInstanceSpace instanceSpace;
-    private Chunk chunk;
+    private final Chunk chunk;
 
 
     public PFColumnarSpace(PFInstanceSpace instanceSpace, Chunk chunk) {

src/main/java/net/minestom/server/entity/pathfinding/PFInstanceSpace.java

@@ -11,8 +11,8 @@ import java.util.concurrent.ConcurrentHashMap;
 
 public class PFInstanceSpace implements IInstanceSpace {
 
-    private Instance instance;
+    private final Instance instance;
-    private Map<Chunk, PFColumnarSpace> chunkSpaceMap = new ConcurrentHashMap<>();
+    private final Map<Chunk, PFColumnarSpace> chunkSpaceMap = new ConcurrentHashMap<>();
 
     public PFInstanceSpace(Instance instance) {
         this.instance = instance;

src/main/java/net/minestom/server/entity/pathfinding/PFPathingEntity.java

@@ -10,7 +10,7 @@ import net.minestom.server.utils.Position;
 
 public class PFPathingEntity implements IPathingEntity {
 
-    private EntityCreature entity;
+    private final EntityCreature entity;
 
     private float searchRange;
     private Position targetPosition;

src/main/java/net/minestom/server/entity/type/decoration/EntityItemFrame.java

@@ -14,7 +14,7 @@ import java.util.function.Consumer;
 // "You have to set both Orientation and Yaw/Pitch accordingly, otherwise it will not work."
 public class EntityItemFrame extends ObjectEntity {
 
-    private ItemFrameOrientation orientation;
+    private final ItemFrameOrientation orientation;
     private ItemStack itemStack;
     private Rotation rotation;
 

src/main/java/net/minestom/server/event/entity/EntityDeathEvent.java

@@ -5,7 +5,7 @@ import net.minestom.server.event.Event;
 
 public class EntityDeathEvent extends Event {
 
-    private Entity entity;
+    private final Entity entity;
     // TODO cause
 
     public EntityDeathEvent(Entity entity) {
@@ -13,6 +13,8 @@ public class EntityDeathEvent extends Event {
     }
 
     /**
+     * Get the killed entity,
+     *
      * @return the entity that died
      */
     public Entity getEntity() {

src/main/java/net/minestom/server/event/entity/EntityItemMergeEvent.java

@@ -9,8 +9,8 @@ import net.minestom.server.item.ItemStack;
  */
 public class EntityItemMergeEvent extends CancellableEvent {
 
-    private ItemEntity source;
+    private final ItemEntity source;
-    private ItemEntity merged;
+    private final ItemEntity merged;
 
     private ItemStack result;
 

src/main/java/net/minestom/server/event/entity/EntityVelocityEvent.java

@@ -6,7 +6,7 @@ import net.minestom.server.utils.Vector;
 
 public class EntityVelocityEvent extends CancellableEvent {
 
-    private Entity entity;
+    private final Entity entity;
     private Vector velocity;
 
     public EntityVelocityEvent(Entity entity, Vector velocity) {

src/main/java/net/minestom/server/event/item/ArmorEquipEvent.java

@@ -7,9 +7,9 @@ import net.minestom.server.utils.item.ItemStackUtils;
 
 public class ArmorEquipEvent extends Event {
 
-    private Entity entity;
+    private final Entity entity;
     private ItemStack armorItem;
-    private ArmorSlot armorSlot;
+    private final ArmorSlot armorSlot;
 
     public ArmorEquipEvent(Entity entity, ItemStack armorItem, ArmorSlot armorSlot) {
         this.entity = entity;

src/main/java/net/minestom/server/event/item/ItemDropEvent.java

@@ -5,7 +5,7 @@ import net.minestom.server.item.ItemStack;
 
 public class ItemDropEvent extends CancellableEvent {
 
-    private ItemStack itemStack;
+    private final ItemStack itemStack;
 
     public ItemDropEvent(ItemStack itemStack) {
         this.itemStack = itemStack;

src/main/java/net/minestom/server/event/item/ItemUpdateStateEvent.java

@@ -6,7 +6,7 @@ import net.minestom.server.item.ItemStack;
 
 public class ItemUpdateStateEvent extends Event {
 
-    private Player player;
+    private final Player player;
     private final Player.Hand hand;
     private final ItemStack itemStack;
     private boolean handAnimation;

src/main/java/net/minestom/server/event/item/PickupExperienceEvent.java

@@ -5,7 +5,7 @@ import net.minestom.server.event.CancellableEvent;
 
 public class PickupExperienceEvent extends CancellableEvent {
 
-    private ExperienceOrb experienceOrb;
+    private final ExperienceOrb experienceOrb;
     private short experienceCount;
 
     public PickupExperienceEvent(ExperienceOrb experienceOrb) {

src/main/java/net/minestom/server/event/item/PickupItemEvent.java

@@ -5,7 +5,7 @@ import net.minestom.server.item.ItemStack;
 
 public class PickupItemEvent extends CancellableEvent {
 
-    private ItemStack itemStack;
+    private final ItemStack itemStack;
 
     public PickupItemEvent(ItemStack itemStack) {
         this.itemStack = itemStack;

src/main/java/net/minestom/server/event/player/PlayerBlockBreakEvent.java

@@ -9,10 +9,10 @@ public class PlayerBlockBreakEvent extends CancellableEvent {
 
     private final Player player;
 
-    private BlockPosition blockPosition;
+    private final BlockPosition blockPosition;
 
-    private short blockStateId;
+    private final short blockStateId;
-    private CustomBlock customBlock;
+    private final CustomBlock customBlock;
 
     private short resultBlockStateId;
     private short resultCustomBlockId;

src/main/java/net/minestom/server/event/player/PlayerBlockInteractEvent.java

@@ -12,8 +12,8 @@ import net.minestom.server.utils.BlockPosition;
 public class PlayerBlockInteractEvent extends CancellableEvent {
 
     private final Player player;
-    private BlockPosition blockPosition;
+    private final BlockPosition blockPosition;
-    private Player.Hand hand;
+    private final Player.Hand hand;
     private final BlockFace blockFace;
 
     /**

src/main/java/net/minestom/server/event/player/PlayerBlockPlaceEvent.java

@@ -17,8 +17,8 @@ public class PlayerBlockPlaceEvent extends CancellableEvent {
     private final Player player;
     private short blockStateId;
     private short customBlockId;
-    private BlockPosition blockPosition;
+    private final BlockPosition blockPosition;
-    private Player.Hand hand;
+    private final Player.Hand hand;
 
     private boolean consumeBlock;
 

src/main/java/net/minestom/server/event/player/PlayerChatEvent.java

@@ -15,7 +15,7 @@ import java.util.function.Function;
 public class PlayerChatEvent extends CancellableEvent {
 
     private final Player sender;
-    private Collection<Player> recipients;
+    private final Collection<Player> recipients;
     private String message;
     private Function<PlayerChatEvent, RichMessage> chatFormat;
 

src/main/java/net/minestom/server/extras/selfmodification/MinestomOverwriteClassLoader.java

@@ -135,7 +135,7 @@ public class MinestomOverwriteClassLoader extends URLClassLoader {
         return true;
     }
 
-    private Class<?> define(String name, byte[] bytes, boolean resolve) throws ClassNotFoundException {
+    private Class<?> define(String name, byte[] bytes, boolean resolve) {
         Class<?> defined = defineClass(name, bytes, 0, bytes.length);
         log.trace("Loaded with code modifiers: " + name);
         if (resolve) {

src/main/java/net/minestom/server/extras/selfmodification/mixins/GlobalPropertyServiceMinestom.java

@@ -46,7 +46,7 @@ public class GlobalPropertyServiceMinestom implements IGlobalPropertyService {
 
     @Override
     public IPropertyKey resolveKey(String name) {
-        return keys.computeIfAbsent(name, k -> new BasicProperty(k));
+        return keys.computeIfAbsent(name, BasicProperty::new);
     }
 
     @Override

src/main/java/net/minestom/server/extras/selfmodification/mixins/MinestomBytecodeProvider.java

@@ -35,7 +35,7 @@ public class MinestomBytecodeProvider implements IClassBytecodeProvider {
     }
 
     @Override
-    public ClassNode getClassNode(String name, boolean runTransformers) throws ClassNotFoundException, IOException {
+    public ClassNode getClassNode(String name, boolean runTransformers) throws ClassNotFoundException {
         return loadNode(name, runTransformers);
     }
 }

src/main/java/net/minestom/server/gamedata/loottables/LootTableContainer.java

@@ -59,7 +59,7 @@ class LootTableContainer {
         }
     }
 
-    private class Entry {
+    private static class Entry {
         private ConditionContainer[] conditions;
         private String type;
         private String name;

src/main/java/net/minestom/server/gamedata/loottables/entries/ItemType.java

@@ -5,7 +5,6 @@ import net.minestom.server.gamedata.loottables.LootTable;
 import net.minestom.server.gamedata.loottables.LootTableEntryType;
 import net.minestom.server.gamedata.loottables.LootTableFunction;
 import net.minestom.server.gamedata.loottables.LootTableManager;
-import net.minestom.server.item.Material;
 import net.minestom.server.registry.Registries;
 import net.minestom.server.utils.NamespaceID;
 

src/main/java/net/minestom/server/gamedata/tags/TagManager.java

@@ -18,14 +18,14 @@ import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
 /**
- * Handles loading and caching of tags
+ * Handles loading and caching of tags.
  */
 public class TagManager {
 
     private static final Logger LOGGER = LoggerFactory.getLogger(TagManager.class);
     private final Gson gson;
-    private Map<NamespaceID, Tag> cache = new ConcurrentHashMap<>();
+    private final Map<NamespaceID, Tag> cache = new ConcurrentHashMap<>();
-    private List<RequiredTag> requiredTags = new LinkedList<>();
+    private final List<RequiredTag> requiredTags = new LinkedList<>();
 
     public TagManager() {
         gson = new GsonBuilder()

src/main/java/net/minestom/server/instance/Chunk.java

@@ -58,8 +58,8 @@ public abstract class Chunk implements Viewable, DataContainer {
     public static final int BIOME_COUNT = 1024; // 4x4x4 blocks group
 
     protected final Instance instance;
-    protected Biome[] biomes;
+    protected final Biome[] biomes;
-    protected int chunkX, chunkZ;
+    protected final int chunkX, chunkZ;
 
     // Options
     private final boolean shouldGenerate;
@@ -70,7 +70,7 @@ public abstract class Chunk implements Viewable, DataContainer {
     private ByteBuf fullDataPacket;
 
     protected volatile boolean loaded = true;
-    protected Set<Player> viewers = new CopyOnWriteArraySet<>();
+    protected final Set<Player> viewers = new CopyOnWriteArraySet<>();
 
     // Path finding
     protected PFColumnarSpace columnarSpace;

src/main/java/net/minestom/server/instance/DynamicChunk.java

@@ -45,15 +45,15 @@ public class DynamicChunk extends Chunk {
 
     // Used to get all blocks with data (no null)
     // Key is still chunk coordinates (see #getBlockIndex)
-    protected Int2ObjectMap<Data> blocksData = new Int2ObjectOpenHashMap<>();
+    protected final Int2ObjectMap<Data> blocksData = new Int2ObjectOpenHashMap<>();
 
     // Contains CustomBlocks' block index which are updatable
-    protected IntSet updatableBlocks = new IntOpenHashSet();
+    protected final IntSet updatableBlocks = new IntOpenHashSet();
     // (block index)/(last update in ms)
-    protected Int2LongMap updatableBlocksLastUpdate = new Int2LongOpenHashMap();
+    protected final Int2LongMap updatableBlocksLastUpdate = new Int2LongOpenHashMap();
 
     // Block entities
-    protected Set<Integer> blockEntities = new CopyOnWriteArraySet<>();
+    protected final Set<Integer> blockEntities = new CopyOnWriteArraySet<>();
 
     public DynamicChunk(Instance instance, Biome[] biomes, int chunkX, int chunkZ) {
         super(instance, biomes, chunkX, chunkZ, true);

src/main/java/net/minestom/server/instance/batch/BlockBatch.java

@@ -22,7 +22,7 @@ import java.util.concurrent.atomic.AtomicInteger;
  */
 public class BlockBatch implements InstanceBatch {
 
-    private InstanceContainer instance;
+    private final InstanceContainer instance;
 
     private final Map<Chunk, List<BlockData>> data = new HashMap<>();
 
@@ -90,9 +90,7 @@ public class BlockBatch implements InstanceBatch {
                         // Execute the callback if this was the last chunk to process
                         if (isLast) {
                             if (callback != null) {
-                                instance.scheduleNextTick(inst -> {
+                                instance.scheduleNextTick(inst -> callback.run());
-                                    callback.run();
-                                });
                             }
                         }
 

src/main/java/net/minestom/server/instance/block/BlockManager.java

@@ -9,12 +9,12 @@ import java.util.Map;
 public class BlockManager {
 
     // custom block id -> custom block
-    private CustomBlock[] customBlocksInternalId = new CustomBlock[Short.MAX_VALUE];
+    private final CustomBlock[] customBlocksInternalId = new CustomBlock[Short.MAX_VALUE];
     // custom block identifier -> custom block
-    private Map<String, CustomBlock> customBlocksId = new HashMap<>();
+    private final Map<String, CustomBlock> customBlocksId = new HashMap<>();
 
     // block id -> block placement rule
-    private BlockPlacementRule[] placementRules = new BlockPlacementRule[Short.MAX_VALUE];
+    private final BlockPlacementRule[] placementRules = new BlockPlacementRule[Short.MAX_VALUE];
 
     /**
      * Registers a {@link CustomBlock}.

src/main/java/net/minestom/server/instance/block/rule/BlockPlacementRule.java

@@ -8,7 +8,7 @@ import net.minestom.server.utils.BlockPosition;
 
 public abstract class BlockPlacementRule {
 
-    private short blockId;
+    private final short blockId;
 
     public BlockPlacementRule(short blockId) {
         this.blockId = blockId;

src/main/java/net/minestom/server/instance/block/rule/vanilla/AxisPlacementRule.java

@@ -9,7 +9,7 @@ import net.minestom.server.utils.BlockPosition;
 
 public class AxisPlacementRule extends BlockPlacementRule {
 
-	Block block;
+    protected final Block block;
 
     public AxisPlacementRule(Block block) {
         super(block);

src/main/java/net/minestom/server/inventory/type/EnchantmentTableInventory.java

@@ -7,10 +7,10 @@ import net.minestom.server.item.Enchantment;
 
 public class EnchantmentTableInventory extends Inventory {
 
-    private short[] levelRequirements = new short[EnchantmentSlot.values().length];
+    private final short[] levelRequirements = new short[EnchantmentSlot.values().length];
     private short seed;
-    private short[] enchantmentShown = new short[EnchantmentSlot.values().length];
+    private final short[] enchantmentShown = new short[EnchantmentSlot.values().length];
-    private short[] enchantmentLevel = new short[EnchantmentSlot.values().length];
+    private final short[] enchantmentLevel = new short[EnchantmentSlot.values().length];
 
     public EnchantmentTableInventory(String title) {
         super(InventoryType.ENCHANTMENT, title);

src/main/java/net/minestom/server/item/metadata/EnchantedBookMeta.java

@@ -10,7 +10,7 @@ import java.util.Map;
 
 public class EnchantedBookMeta implements ItemMeta {
 
-    private Map<Enchantment, Short> storedEnchantmentMap = new HashMap<>();
+    private final Map<Enchantment, Short> storedEnchantmentMap = new HashMap<>();
 
     /**
      * Gets the stored enchantment map.

src/main/java/net/minestom/server/item/metadata/MapMeta.java

@@ -202,10 +202,10 @@ public class MapMeta implements ItemMeta {
     }
 
     public static class MapDecoration {
-        private String id;
+        private final String id;
-        private byte type;
+        private final byte type;
-        private byte x, z;
+        private final byte x, z;
-        private double rotation;
+        private final double rotation;
 
         public MapDecoration(String id, byte type, byte x, byte z, double rotation) {
             this.id = id;

src/main/java/net/minestom/server/item/metadata/PotionMeta.java

@@ -21,7 +21,7 @@ import java.util.concurrent.CopyOnWriteArrayList;
 public class PotionMeta implements ItemMeta {
 
     private PotionType potionType;
-    private List<CustomPotionEffect> customPotionEffects = new CopyOnWriteArrayList<>();
+    private final List<CustomPotionEffect> customPotionEffects = new CopyOnWriteArrayList<>();
 
     private boolean hasColor;
     private byte red, green, blue;

src/main/java/net/minestom/server/listener/UseItemListener.java

@@ -83,9 +83,7 @@ public class UseItemListener {
 
             // Eating code, contains the eating time customisation
             PlayerPreEatEvent playerPreEatEvent = new PlayerPreEatEvent(player, itemStack, player.getDefaultEatingTime());
-            player.callCancellableEvent(PlayerPreEatEvent.class, playerPreEatEvent, () -> {
+            player.callCancellableEvent(PlayerPreEatEvent.class, playerPreEatEvent, () -> player.refreshEating(true, playerPreEatEvent.getEatingTime()));
-                player.refreshEating(true, playerPreEatEvent.getEatingTime());
-            });
         }
 
         if (itemAnimationType != null) {

src/main/java/net/minestom/server/listener/manager/PacketListenerManager.java

@@ -14,7 +14,7 @@ public class PacketListenerManager {
 
     private static final ConnectionManager CONNECTION_MANAGER = MinecraftServer.getConnectionManager();
 
-    private Map<Class<? extends ClientPlayPacket>, PacketListenerConsumer> listeners = new ConcurrentHashMap<>();
+    private final Map<Class<? extends ClientPlayPacket>, PacketListenerConsumer> listeners = new ConcurrentHashMap<>();
 
     public PacketListenerManager() {
         setListener(ClientKeepAlivePacket.class, KeepAliveListener::listener);

src/main/java/net/minestom/server/network/ConnectionManager.java

@@ -19,17 +19,17 @@ import java.util.function.Function;
  */
 public final class ConnectionManager {
 
-    private Set<Player> players = new CopyOnWriteArraySet<>();
+    private final Set<Player> players = new CopyOnWriteArraySet<>();
-    private Map<PlayerConnection, Player> connectionPlayerMap = Collections.synchronizedMap(new HashMap<>());
+    private final Map<PlayerConnection, Player> connectionPlayerMap = Collections.synchronizedMap(new HashMap<>());
 
     // All the consumers to call once a packet is received
-    private List<PacketConsumer> receivePacketConsumers = new CopyOnWriteArrayList<>();
+    private final List<PacketConsumer> receivePacketConsumers = new CopyOnWriteArrayList<>();
     // The uuid provider once a player login
     private UuidProvider uuidProvider;
     // The player provider to have your own Player implementation
     private PlayerProvider playerProvider;
     // The consumers to call once a player connect, mostly used to init events
-    private List<Consumer<Player>> playerInitializations = new CopyOnWriteArrayList<>();
+    private final List<Consumer<Player>> playerInitializations = new CopyOnWriteArrayList<>();
 
     /**
      * Gets the {@link Player} linked to a {@link PlayerConnection}.

src/main/java/net/minestom/server/network/netty/codec/LegacyPingHandler.java

@@ -15,7 +15,7 @@ public class LegacyPingHandler extends ChannelInboundHandlerAdapter {
     private ByteBuf buf;
 
     @Override
-    public void channelRead(ChannelHandlerContext ctx, Object object) throws Exception {
+    public void channelRead(ChannelHandlerContext ctx, Object object) {
         ByteBuf buf = (ByteBuf) object;
 
         if (this.buf != null) {

src/main/java/net/minestom/server/network/netty/codec/PacketDecoder.java

@@ -11,7 +11,7 @@ import java.util.List;
 public class PacketDecoder extends ByteToMessageDecoder {
 
     @Override
-    protected void decode(ChannelHandlerContext ctx, ByteBuf buf, List<Object> list) throws Exception {
+    protected void decode(ChannelHandlerContext ctx, ByteBuf buf, List<Object> list) {
         if (buf.readableBytes() > 0) {
             list.add(new InboundPacket(Utils.readVarInt(buf), buf));
         }

src/main/java/net/minestom/server/network/netty/codec/PacketEncoder.java

@@ -9,7 +9,7 @@ import net.minestom.server.utils.PacketUtils;
 public class PacketEncoder extends MessageToByteEncoder<ServerPacket> {
 
     @Override
-    protected void encode(ChannelHandlerContext ctx, ServerPacket packet, ByteBuf buf) throws Exception {
+    protected void encode(ChannelHandlerContext ctx, ServerPacket packet, ByteBuf buf) {
         PacketUtils.writePacket(buf, packet);
     }
 

src/main/java/net/minestom/server/network/packet/server/play/ChatMessagePacket.java

@@ -8,9 +8,9 @@ import java.util.UUID;
 
 public class ChatMessagePacket implements ServerPacket {
 
-    private String jsonMessage;
+    public String jsonMessage;
-    private Position position;
+    public Position position;
-    private UUID uuid;
+    public UUID uuid;
 
     public ChatMessagePacket(String jsonMessage, Position position, UUID uuid) {
         this.jsonMessage = jsonMessage;

src/main/java/net/minestom/server/network/packet/server/play/WindowItemsPacket.java

@@ -20,8 +20,7 @@ public class WindowItemsPacket implements ServerPacket {
         }
 
         writer.writeShort((short) items.length);
-        for (int i = 0; i < items.length; i++) {
+        for (ItemStack item : items) {
-            ItemStack item = items[i];
             writer.writeItemStack(item);
         }
     }

src/main/java/net/minestom/server/network/packet/server/play/WorldBorderPacket.java

@@ -35,7 +35,7 @@ public class WorldBorderPacket implements ServerPacket {
 
     public static class WBSetSize extends WBAction {
 
-        public double diameter;
+        public final double diameter;
 
         public WBSetSize(double diameter) {
             this.diameter = diameter;
@@ -49,9 +49,9 @@ public class WorldBorderPacket implements ServerPacket {
 
     public static class WBLerpSize extends WBAction {
 
-        public double oldDiameter;
+        public final double oldDiameter;
-        public double newDiameter;
+        public final double newDiameter;
-        public long speed;
+        public final long speed;
 
         public WBLerpSize(double oldDiameter, double newDiameter, long speed) {
             this.oldDiameter = oldDiameter;
@@ -69,7 +69,7 @@ public class WorldBorderPacket implements ServerPacket {
 
     public static class WBSetCenter extends WBAction {
 
-        public double x, z;
+        public final double x, z;
 
         public WBSetCenter(double x, double z) {
             this.x = x;
@@ -85,13 +85,13 @@ public class WorldBorderPacket implements ServerPacket {
 
     public static class WBInitialize extends WBAction {
 
-        public double x, z;
+        public final double x, z;
-        public double oldDiameter;
+        public final double oldDiameter;
-        public double newDiameter;
+        public final double newDiameter;
-        public long speed;
+        public final long speed;
-        public int portalTeleportBoundary;
+        public final int portalTeleportBoundary;
-        public int warningTime;
+        public final int warningTime;
-        public int warningBlocks;
+        public final int warningBlocks;
 
         public WBInitialize(double x, double z, double oldDiameter, double newDiameter, long speed,
                             int portalTeleportBoundary, int warningTime, int warningBlocks) {
@@ -120,7 +120,7 @@ public class WorldBorderPacket implements ServerPacket {
 
     public static class WBSetWarningTime extends WBAction {
 
-        public int warningTime;
+        public final int warningTime;
 
         public WBSetWarningTime(int warningTime) {
             this.warningTime = warningTime;
@@ -134,7 +134,7 @@ public class WorldBorderPacket implements ServerPacket {
 
     public static class WBSetWarningBlocks extends WBAction {
 
-        public int warningBlocks;
+        public final int warningBlocks;
 
         public WBSetWarningBlocks(int warningBlocks) {
             this.warningBlocks = warningBlocks;

src/main/java/net/minestom/server/thread/PerGroupChunkProvider.java

@@ -7,10 +7,7 @@ import it.unimi.dsi.fastutil.longs.LongSet;
 import net.minestom.server.instance.Instance;
 import net.minestom.server.utils.chunk.ChunkUtils;
 
-import java.util.ArrayList;
+import java.util.*;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.Future;
@@ -78,7 +75,7 @@ public class PerGroupChunkProvider extends ThreadProvider {
         }
 
         // The size of the final list, used as the initial capacity
-        final int size = neighboursGroups.stream().mapToInt(value -> value.size()).sum() + 1;
+        final int size = neighboursGroups.stream().mapToInt(Set::size).sum() + 1;
 
         // Represent the merged group of all the neighbours
         LongSet finalGroup = new LongArraySet(size);
@@ -135,9 +132,7 @@ public class PerGroupChunkProvider extends ThreadProvider {
             }));
 
             // Update all the chunks
-            instanceMap.keySet().forEach(chunksIndexes -> {
+            instanceMap.keySet().forEach(chunksIndexes -> futures.add(pool.submit(() -> {
-
-                futures.add(pool.submit(() -> {
                 // Wait for the instance to be updated
                 // Needed because the instance tick is used to unload waiting chunks
                 try {
@@ -148,8 +143,7 @@ public class PerGroupChunkProvider extends ThreadProvider {
 
                 // Tick all this chunk group
                 chunksIndexes.forEach((long chunkIndex) -> processChunkTick(instance, chunkIndex, time));
-                }));
+            })));
-            });
         });
         return futures;
     }

src/main/java/net/minestom/server/thread/PerInstanceThreadProvider.java

@@ -12,11 +12,11 @@ import java.util.Map;
 import java.util.concurrent.Future;
 
 /**
- * Separate work between instance (1 instance = 1 thread execution)
+ * Separates work between instance (1 instance = 1 thread execution).
  */
 public class PerInstanceThreadProvider extends ThreadProvider {
 
-    private Map<Instance, LongSet> instanceChunkMap = new HashMap<>();
+    private final Map<Instance, LongSet> instanceChunkMap = new HashMap<>();
 
     @Override
     public void onInstanceCreate(Instance instance) {
@@ -49,15 +49,12 @@ public class PerInstanceThreadProvider extends ThreadProvider {
     public List<Future<?>> update(long time) {
         List<Future<?>> futures = new ArrayList<>();
 
-        instanceChunkMap.forEach((instance, chunkIndexes) -> {
+        instanceChunkMap.forEach((instance, chunkIndexes) -> futures.add(pool.submit(() -> {
-
-            futures.add(pool.submit(() -> {
             // Tick instance
             updateInstance(instance, time);
             // Tick chunks
             chunkIndexes.forEach((long chunkIndex) -> processChunkTick(instance, chunkIndex, time));
-            }));
+        })));
-        });
         return futures;
     }
 

src/main/java/net/minestom/server/utils/ArrayUtils.java

@@ -43,8 +43,7 @@ public final class ArrayUtils {
         for (int i = 0; i < a.length; i++) {
             final long aValue = a[i];
             boolean contains = false;
-            for (int n = 0; n < b.length; n++) {
+            for (final long bValue : b) {
-                final long bValue = b[n];
                 if (bValue == aValue) {
                     contains = true;
                     break;

src/main/java/net/minestom/server/utils/NamespaceID.java

@@ -4,7 +4,6 @@ import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Objects;
-import java.util.regex.Pattern;
 
 /**
  * Represents a namespaced ID

src/main/java/net/minestom/server/utils/Utils.java

@@ -135,8 +135,8 @@ public final class Utils {
         }
         final long[] data = encodeBlocks(blocksData, bitsPerEntry);
         writeVarIntBuf(buffer, data.length);
-        for (int i = 0; i < data.length; i++) {
+        for (long datum : data) {
-            buffer.writeLong(data[i]);
+            buffer.writeLong(datum);
         }
     }