Skip-event-if-no-listeners

patches/server/0051-Skip-event-if-no-listeners.patch

@@ -0,0 +1,31 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: lilingfengdev <145678359+lilingfengdev@users.noreply.github.com>
+Date: Wed, 17 Jan 2024 18:16:38 +0800
+Subject: [PATCH] Skip event if no listeners
+
+
+diff --git a/src/main/java/io/papermc/paper/plugin/manager/PaperEventManager.java b/src/main/java/io/papermc/paper/plugin/manager/PaperEventManager.java
+index 06dfd0b27ac0006a2be07f54a0702519a691c6ec..90b40040b2dc0e8a481515a9b139cf1277578545 100644
+--- a/src/main/java/io/papermc/paper/plugin/manager/PaperEventManager.java
++++ b/src/main/java/io/papermc/paper/plugin/manager/PaperEventManager.java
+@@ -35,6 +35,10 @@ class PaperEventManager {
+ 
+     // SimplePluginManager
+     public void callEvent(@NotNull Event event) {
++        // Leaf start - Skip event if no listeners
++        RegisteredListener[] listeners = event.getHandlers().getRegisteredListeners();
++        if (listeners.length == 0) return;
++        // Leaf end
+         // KTP start - Optimise spigot event bus
+         if (event.asynchronous() != net.kyori.adventure.util.TriState.NOT_SET) {
+         final boolean onPrimaryThread = this.server.isPrimaryThread();
+@@ -47,9 +51,6 @@ class PaperEventManager {
+         // KTP stop - Optimise spigot event bus
+         }
+ 
+-        HandlerList handlers = event.getHandlers();
+-        RegisteredListener[] listeners = handlers.getRegisteredListeners();
+-
+         for (RegisteredListener registration : listeners) {
+             if (!registration.getPlugin().isEnabled()) {
+                 continue;