From c0e39a8677454538f878b96e74207423a901a128 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Mon, 28 Mar 2016 19:55:45 -0400
Subject: [PATCH] Only process BlockPhysicsEvent if a plugin has a listener

Saves on some object allocation and processing when no plugin listens to this

diff --git a/src/main/java/net/minecraft/server/BlockPlant.java b/src/main/java/net/minecraft/server/BlockPlant.java
index 9bf42bb5e..0526af776 100644
--- a/src/main/java/net/minecraft/server/BlockPlant.java
+++ b/src/main/java/net/minecraft/server/BlockPlant.java
@@ -16,7 +16,7 @@ public class BlockPlant extends Block {
     public IBlockData updateState(IBlockData iblockdata, EnumDirection enumdirection, IBlockData iblockdata1, GeneratorAccess generatoraccess, BlockPosition blockposition, BlockPosition blockposition1) {
         // CraftBukkit start
         if (!iblockdata.canPlace(generatoraccess, blockposition)) {
-            if (!org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(generatoraccess, blockposition).isCancelled()) {
+            if (!(generatoraccess instanceof WorldServer && ((WorldServer) generatoraccess).hasPhysicsEvent) || !org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(generatoraccess, blockposition).isCancelled()) { // Paper
                 return Blocks.AIR.getBlockData();
             }
         }
diff --git a/src/main/java/net/minecraft/server/BlockTallPlant.java b/src/main/java/net/minecraft/server/BlockTallPlant.java
index 469a3be05..f2c429f22 100644
--- a/src/main/java/net/minecraft/server/BlockTallPlant.java
+++ b/src/main/java/net/minecraft/server/BlockTallPlant.java
@@ -55,7 +55,7 @@ public class BlockTallPlant extends BlockPlant {
     @Override
     public void a(World world, BlockPosition blockposition, IBlockData iblockdata, EntityHuman entityhuman) {
         // CraftBukkit start
-        if (org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, blockposition).isCancelled()) {
+        if (((WorldServer)world).hasPhysicsEvent && org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, blockposition).isCancelled()) { // Paper
             return;
         }
         // CraftBukkit end
diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 454e28fc4..40b9bff98 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -1096,6 +1096,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
         // CraftBukkit - dropTickTime
         for (Iterator iterator = this.getWorlds().iterator(); iterator.hasNext();) {
             WorldServer worldserver = (WorldServer) iterator.next();
+            worldserver.hasPhysicsEvent =  org.bukkit.event.block.BlockPhysicsEvent.getHandlerList().getRegisteredListeners().length > 0; // Paper
             i = SystemUtils.getMonotonicNanos();
             if (true || worldserver.worldProvider.getDimensionManager() == DimensionManager.OVERWORLD || this.getAllowNether()) { // CraftBukkit
                 this.methodProfiler.a(() -> {
diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index 6e655d292..7f0a338d6 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -444,7 +444,7 @@ public abstract class World implements IIBlockAccess, GeneratorAccess, AutoClose
                 // CraftBukkit start
                 iblockdata1.b(this, blockposition, j); // Don't call an event for the old block to limit event spam
                 CraftWorld world = ((WorldServer) this).getWorld();
-                if (world != null) {
+                if (world != null && ((WorldServer)this).hasPhysicsEvent) { // Paper
                     BlockPhysicsEvent event = new BlockPhysicsEvent(world.getBlockAt(blockposition.getX(), blockposition.getY(), blockposition.getZ()), CraftBlockData.fromData(iblockdata));
                     this.getServer().getPluginManager().callEvent(event);
 
@@ -556,7 +556,7 @@ public abstract class World implements IIBlockAccess, GeneratorAccess, AutoClose
             try {
                 // CraftBukkit start
                 CraftWorld world = ((WorldServer) this).getWorld();
-                if (world != null) {
+                if (world != null && ((WorldServer)this).hasPhysicsEvent) { // Paper
                     BlockPhysicsEvent event = new BlockPhysicsEvent(world.getBlockAt(blockposition.getX(), blockposition.getY(), blockposition.getZ()), CraftBlockData.fromData(iblockdata), world.getBlockAt(blockposition1.getX(), blockposition1.getY(), blockposition1.getZ()));
                     this.getServer().getPluginManager().callEvent(event);
 
diff --git a/src/main/java/net/minecraft/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
index 727faa35d..7c3d2d5de 100644
--- a/src/main/java/net/minecraft/server/WorldServer.java
+++ b/src/main/java/net/minecraft/server/WorldServer.java
@@ -68,6 +68,7 @@ public class WorldServer extends World {
 
     // CraftBukkit start
     private int tickPosition;
+    boolean hasPhysicsEvent = true; // Paper
 
     // Add env and gen to constructor
     public WorldServer(MinecraftServer minecraftserver, Executor executor, WorldNBTStorage worldnbtstorage, WorldData worlddata, DimensionManager dimensionmanager, GameProfilerFiller gameprofilerfiller, WorldLoadListener worldloadlistener, org.bukkit.World.Environment env, org.bukkit.generator.ChunkGenerator gen) {
-- 
2.21.0