From a8c1c732829e13c6f60844af04b3274ae7f04f5c Mon Sep 17 00:00:00 2001
From: themode <themode@outlook.fr>
Date: Sun, 22 Nov 2020 17:40:57 +0100
Subject: [PATCH] Use of a synchronized wrapper for InstanceContainer chunks
 map

---
 .../server/instance/InstanceContainer.java    | 37 +++++++------------
 1 file changed, 14 insertions(+), 23 deletions(-)

diff --git a/src/main/java/net/minestom/server/instance/InstanceContainer.java b/src/main/java/net/minestom/server/instance/InstanceContainer.java
index ae816699f..0641cb261 100644
--- a/src/main/java/net/minestom/server/instance/InstanceContainer.java
+++ b/src/main/java/net/minestom/server/instance/InstanceContainer.java
@@ -1,6 +1,7 @@
 package net.minestom.server.instance;
 
 import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
+import it.unimi.dsi.fastutil.longs.Long2ObjectMaps;
 import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
 import net.minestom.server.MinecraftServer;
 import net.minestom.server.data.Data;
@@ -57,7 +58,7 @@ public class InstanceContainer extends Instance {
     // the chunk generator used, can be null
     private ChunkGenerator chunkGenerator;
     // (chunk index -> chunk) map, contains all the chunks in the instance
-    private final Long2ObjectMap<Chunk> chunks = new Long2ObjectOpenHashMap<>();
+    private final Long2ObjectMap<Chunk> chunks = Long2ObjectMaps.synchronize(new Long2ObjectOpenHashMap<>());
     // contains all the chunks to remove during the next instance tick
     protected final Set<Chunk> scheduledChunksToRemove = new HashSet<>();
 
@@ -451,10 +452,8 @@ public class InstanceContainer extends Instance {
     @Override
     public Chunk getChunk(int chunkX, int chunkZ) {
         final long index = ChunkUtils.getChunkIndex(chunkX, chunkZ);
-        synchronized (chunks) {
-            final Chunk chunk = chunks.get(index);
-            return ChunkUtils.isLoaded(chunk) ? chunk : null;
-        }
+        final Chunk chunk = chunks.get(index);
+        return ChunkUtils.isLoaded(chunk) ? chunk : null;
     }
 
     /**
@@ -495,10 +494,8 @@ public class InstanceContainer extends Instance {
 
     @Override
     public void saveChunksToStorage(@Nullable Runnable callback) {
-        synchronized (chunks) {
-            Collection<Chunk> chunksCollection = chunks.values();
-            this.chunkLoader.saveChunks(chunksCollection, callback);
-        }
+        Collection<Chunk> chunksCollection = chunks.values();
+        this.chunkLoader.saveChunks(chunksCollection, callback);
     }
 
     @Override
@@ -645,16 +642,14 @@ public class InstanceContainer extends Instance {
         copiedInstance.srcInstance = this;
         copiedInstance.lastBlockChangeTime = lastBlockChangeTime;
 
-        synchronized (chunks) {
-            for (Chunk chunk : chunks.values()) {
-                final int chunkX = chunk.getChunkX();
-                final int chunkZ = chunk.getChunkZ();
+        for (Chunk chunk : chunks.values()) {
+            final int chunkX = chunk.getChunkX();
+            final int chunkZ = chunk.getChunkZ();
 
-                final Chunk copiedChunk = chunk.copy(chunkX, chunkZ);
+            final Chunk copiedChunk = chunk.copy(chunkX, chunkZ);
 
-                copiedInstance.cacheChunk(copiedChunk);
-                UPDATE_MANAGER.signalChunkLoad(copiedInstance, chunkX, chunkZ);
-            }
+            copiedInstance.cacheChunk(copiedChunk);
+            UPDATE_MANAGER.signalChunkLoad(copiedInstance, chunkX, chunkZ);
         }
 
         return copiedInstance;
@@ -701,9 +696,7 @@ public class InstanceContainer extends Instance {
      */
     public void cacheChunk(@NotNull Chunk chunk) {
         final long index = ChunkUtils.getChunkIndex(chunk.getChunkX(), chunk.getChunkZ());
-        synchronized (chunks) {
-            this.chunks.put(index, chunk);
-        }
+        this.chunks.put(index, chunk);
     }
 
     @Override
@@ -833,9 +826,7 @@ public class InstanceContainer extends Instance {
                 });
 
                 // Clear cache
-                synchronized (chunks) {
-                    this.chunks.remove(index);
-                }
+                this.chunks.remove(index);
                 synchronized (chunkEntities) {
                     this.chunkEntities.remove(index);
                 }