Use fastutil treemap

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

@@ -4,8 +4,6 @@ import net.minestom.server.Tickable;
 import net.minestom.server.Viewable;
 import net.minestom.server.coordinate.Point;
 import net.minestom.server.coordinate.Vec;
-import net.minestom.server.data.Data;
-import net.minestom.server.data.DataContainer;
 import net.minestom.server.entity.Player;
 import net.minestom.server.entity.pathfinding.PFColumnarSpace;
 import net.minestom.server.event.EventDispatcher;
@@ -42,8 +40,7 @@ import java.util.concurrent.ConcurrentHashMap;
  * You generally want to avoid storing references of this object as this could lead to a huge memory leak,
  * you should store the chunk coordinates instead.
  */
-public abstract class Chunk implements BlockGetter, BlockSetter, Viewable, Tickable, TagHandler, DataContainer {
-
+public abstract class Chunk implements BlockGetter, BlockSetter, Viewable, Tickable, TagHandler {
     public static final int CHUNK_SIZE_X = 16;
     public static final int CHUNK_SIZE_Z = 16;
     public static final int CHUNK_SECTION_SIZE = 16;
@@ -68,7 +65,6 @@ public abstract class Chunk implements BlockGetter, BlockSetter, Viewable, Ticka
 
     // Data
     private final NBTCompound nbt = new NBTCompound();
-    protected Data data;
 
     public Chunk(@NotNull Instance instance, @Nullable Biome[] biomes, int chunkX, int chunkZ, boolean shouldGenerate) {
         this.identifier = UUID.randomUUID();
@@ -102,7 +98,7 @@ public abstract class Chunk implements BlockGetter, BlockSetter, Viewable, Ticka
     @Override
     public abstract void setBlock(int x, int y, int z, @NotNull Block block);
 
-    public abstract @NotNull TreeMap<Integer, Section> getSections();
+    public abstract @NotNull Map<Integer, Section> getSections();
 
     public abstract @NotNull Section getSection(int section);
 
@@ -373,17 +369,6 @@ public abstract class Chunk implements BlockGetter, BlockSetter, Viewable, Ticka
         tag.write(nbt, value);
     }
 
-    @Nullable
-    @Override
-    public Data getData() {
-        return data;
-    }
-
-    @Override
-    public void setData(@Nullable Data data) {
-        this.data = data;
-    }
-
     /**
      * Sends the chunk data to {@code player}.
      *

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

@@ -1,6 +1,7 @@
 package net.minestom.server.instance;
 
 import com.extollit.gaming.ai.path.model.ColumnarOcclusionFieldList;
+import it.unimi.dsi.fastutil.ints.Int2ObjectAVLTreeMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import net.minestom.server.coordinate.Vec;
 import net.minestom.server.entity.pathfinding.PFBlock;
@@ -11,12 +12,10 @@ import net.minestom.server.utils.chunk.ChunkUtils;
 import net.minestom.server.world.biomes.Biome;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.jglrxavpok.hephaistos.nbt.NBTCompound;
 
 import java.lang.ref.SoftReference;
 import java.util.Map;
 import java.util.Objects;
-import java.util.TreeMap;
 
 /**
  * Represents a {@link Chunk} which store each individual block in memory.
@@ -25,7 +24,7 @@ import java.util.TreeMap;
  */
 public class DynamicChunk extends Chunk {
 
-    protected final TreeMap<Integer, Section> sectionMap = new TreeMap<>();
+    protected final Int2ObjectAVLTreeMap<Section> sectionMap = new Int2ObjectAVLTreeMap<>();
 
     // Key = ChunkUtils#getBlockIndex
     protected final Int2ObjectOpenHashMap<Block> entries = new Int2ObjectOpenHashMap<>();
@@ -69,7 +68,7 @@ public class DynamicChunk extends Chunk {
     }
 
     @Override
-    public @NotNull TreeMap<Integer, Section> getSections() {
+    public @NotNull Map<Integer, Section> getSections() {
         return sectionMap;
     }
 
@@ -129,7 +128,7 @@ public class DynamicChunk extends Chunk {
         packet.biomes = biomes;
         packet.chunkX = chunkX;
         packet.chunkZ = chunkZ;
-        packet.sections = (Map<Integer, Section>) sectionMap.clone(); // TODO deep clone
+        packet.sections = sectionMap.clone(); // TODO deep clone
         packet.entries = entries.clone();
 
         this.cachedPacketTime = getLastChangeTime();
@@ -141,8 +140,8 @@ public class DynamicChunk extends Chunk {
     @Override
     public Chunk copy(@NotNull Instance instance, int chunkX, int chunkZ) {
         DynamicChunk dynamicChunk = new DynamicChunk(instance, biomes.clone(), chunkX, chunkZ);
-        for (var entry : sectionMap.entrySet()) {
-            dynamicChunk.sectionMap.put(entry.getKey(), entry.getValue().clone());
+        for (var entry : sectionMap.int2ObjectEntrySet()) {
+            dynamicChunk.sectionMap.put(entry.getIntKey(), entry.getValue().clone());
         }
         dynamicChunk.entries.putAll(entries);
         return dynamicChunk;

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

@@ -5,7 +5,6 @@ import io.netty.buffer.Unpooled;
 import it.unimi.dsi.fastutil.ints.Int2LongRBTreeMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import net.minestom.server.MinecraftServer;
-import net.minestom.server.instance.DynamicChunk;
 import net.minestom.server.instance.Section;
 import net.minestom.server.instance.block.Block;
 import net.minestom.server.instance.block.BlockHandler;
@@ -133,7 +132,7 @@ public class ChunkDataPacket implements ServerPacket, CacheablePacket {
                 final int index = entry.getKey();
                 final var block = entry.getValue();
                 final BlockHandler handler = block.handler();
-                if(handler == null)
+                if (handler == null)
                     continue;
                 final var blockEntityTags = handler.getBlockEntityTags();
                 if (blockEntityTags.isEmpty()) // Verify if the block should be sent as block entity to client