From 452b0cd832ff24ce65a8d5bab77db2eb4a3665ab Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sat, 11 Jan 2020 21:50:56 -0800
Subject: [PATCH] Optimise IEntityAccess#getPlayerByUUID

Use the world entity map instead of iterating over all players

diff --git a/src/main/java/net/minecraft/server/IEntityAccess.java b/src/main/java/net/minecraft/server/IEntityAccess.java
index d5c284cdd..4157e50e4 100644
--- a/src/main/java/net/minecraft/server/IEntityAccess.java
+++ b/src/main/java/net/minecraft/server/IEntityAccess.java
@@ -219,6 +219,12 @@ public interface IEntityAccess {
 
     @Nullable
     default EntityHuman b(UUID uuid) {
+        // Paper start - allow WorldServer to override
+        return this.getPlayerByUUID(uuid);
+    }
+    @Nullable
+    default EntityHuman getPlayerByUUID(UUID uuid) {
+        // Paper end
         for (int i = 0; i < this.getPlayers().size(); ++i) {
             EntityHuman entityhuman = (EntityHuman) this.getPlayers().get(i);
 
diff --git a/src/main/java/net/minecraft/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
index 32512e5cc..0b3f6b8ba 100644
--- a/src/main/java/net/minecraft/server/WorldServer.java
+++ b/src/main/java/net/minecraft/server/WorldServer.java
@@ -82,6 +82,15 @@ public class WorldServer extends World {
         return new Throwable(entity + " Added to world at " + new java.util.Date());
     }
 
+    // Paper start - optimise getPlayerByUUID
+    @Nullable
+    @Override
+    public EntityHuman getPlayerByUUID(UUID uuid) {
+        Entity player = this.entitiesByUUID.get(uuid);
+        return (player instanceof EntityHuman) ? (EntityHuman)player : null;
+    }
+    // Paper end
+
     // Paper start - Asynchronous IO
     public final com.destroystokyo.paper.io.PaperFileIOThread.ChunkDataController poiDataController = new com.destroystokyo.paper.io.PaperFileIOThread.ChunkDataController() {
         @Override
-- 
2.25.0.windows.1