From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Martijn Muijsers <martijnmuijsers@live.nl>
Date: Wed, 30 Nov 2022 21:02:43 +0100
Subject: [PATCH] Replace class map with optimized collection

License: LGPL-3.0 (https://www.gnu.org/licenses/lgpl-3.0.html)
Gale - https://galemc.org

This patch is based on the following mixin:
"me/jellysquid/mods/lithium/mixin/collections/entity_by_type/TypeFilterableListMixin.java"
By: 2No2Name <2No2Name@web.de>
As part of: Lithium (https://github.com/CaffeineMC/lithium-fabric)
Licensed under: LGPL-3.0 (https://www.gnu.org/licenses/lgpl-3.0.html)

diff --git a/src/main/java/net/minecraft/util/ClassInstanceMultiMap.java b/src/main/java/net/minecraft/util/ClassInstanceMultiMap.java
index 038710ba934a9a57815dfe9f414b98223b848385..cd28174187133550e418c0e748ce8a06739d0146 100644
--- a/src/main/java/net/minecraft/util/ClassInstanceMultiMap.java
+++ b/src/main/java/net/minecraft/util/ClassInstanceMultiMap.java
@@ -4,6 +4,8 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterators;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
+import it.unimi.dsi.fastutil.objects.Reference2ReferenceOpenHashMap;
+
 import java.util.AbstractCollection;
 import java.util.Collection;
 import java.util.Collections;
@@ -14,7 +16,7 @@ import java.util.Map.Entry;
 import net.minecraft.Util;
 
 public class ClassInstanceMultiMap<T> extends AbstractCollection<T> {
-    private final Map<Class<?>, List<T>> byClass = Maps.newHashMap();
+    private final Map<Class<?>, List<T>> byClass = new Reference2ReferenceOpenHashMap<>(2); // Gale - Lithium - replace class map with optimized collection
     private final Class<T> baseClass;
     private final List<T> allInstances = Lists.newArrayList();