Optimize isEmpty() to remove Map lookup

Every call to .isEmpty() made a horribly wasteful map lookup just to get the
reference to the Air Item for checking.

We will now cache a copy of that item
This commit is contained in:
Aikar 2016-12-21 04:21:42 -05:00
parent a18f763412
commit 98e7d01ce8

View File

@ -0,0 +1,31 @@
From ae097c16d9540ec79890ddb5ba0efe693874621a Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 21 Dec 2016 03:48:29 -0500
Subject: [PATCH] Optimize ItemStack.isEmpty()
Remove hashMap lookup every check, simplify code to remove ternary
diff --git a/src/main/java/net/minecraft/server/ItemStack.java b/src/main/java/net/minecraft/server/ItemStack.java
index c8694e8b9..6db93b953 100644
--- a/src/main/java/net/minecraft/server/ItemStack.java
+++ b/src/main/java/net/minecraft/server/ItemStack.java
@@ -112,9 +112,15 @@ public final class ItemStack {
this.F();
}
+ // Paper start - optimize isEmpty
+ private static Item airItem;
public boolean isEmpty() {
- return this == ItemStack.a ? true : (this.item != null && this.item != Item.getItemOf(Blocks.AIR) ? (this.count <= 0 ? true : this.damage < -32768 || this.damage > '\uffff') : true);
+ if (airItem == null) {
+ airItem = Item.REGISTRY.get(new MinecraftKey("air"));
+ }
+ return this == ItemStack.a || this.item == null || this.item == airItem || (this.count <= 0 || (this.damage < -32768 || this.damage > '\uffff'));
}
+ // Paper end
public static void a(DataConverterManager dataconvertermanager) {
dataconvertermanager.a(DataConverterTypes.ITEM_INSTANCE, (DataInspector) (new DataInspectorBlockEntity()));
--
2.11.0