From 0000000000000000000000000000000000000000 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/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 2c295e070a0418c7d3bc4a4a531df699acadb0ff..555b99c45e0785750c48b0db2bc0b8da98c52295 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -1282,6 +1282,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
 
         while (iterator.hasNext()) {
             WorldServer worldserver = (WorldServer) iterator.next();
+            worldserver.hasPhysicsEvent =  org.bukkit.event.block.BlockPhysicsEvent.getHandlerList().getRegisteredListeners().length > 0; // Paper
 
             this.methodProfiler.a(() -> {
                 return worldserver + " " + worldserver.getDimensionKey().a();
diff --git a/src/main/java/net/minecraft/server/level/WorldServer.java b/src/main/java/net/minecraft/server/level/WorldServer.java
index 3403ed91e7ec98116438398fb7247e7f05171feb..addbb868ac43538b9fc468eb2601ffc9f974fa37 100644
--- a/src/main/java/net/minecraft/server/level/WorldServer.java
+++ b/src/main/java/net/minecraft/server/level/WorldServer.java
@@ -196,6 +196,7 @@ public class WorldServer extends World implements GeneratorAccessSeed {
     private int tickPosition;
     public final Convertable.ConversionSession convertable;
     public final UUID uuid;
+    public boolean hasPhysicsEvent = true; // Paper
 
     @Override public Chunk getChunkIfLoaded(int x, int z) { // Paper - this was added in world too but keeping here for NMS ABI
         return this.chunkProvider.getChunkAt(x, z, false);
diff --git a/src/main/java/net/minecraft/world/level/World.java b/src/main/java/net/minecraft/world/level/World.java
index a22be13b097052b2a88707c9436b88c84298e46b..9236e480d21340d4295caa16dae34363e182f483 100644
--- a/src/main/java/net/minecraft/world/level/World.java
+++ b/src/main/java/net/minecraft/world/level/World.java
@@ -458,7 +458,7 @@ public abstract class World implements GeneratorAccess, AutoCloseable {
                 // CraftBukkit start
                 iblockdata1.b(this, blockposition, k, j - 1); // 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);
 
@@ -560,7 +560,7 @@ public abstract class World implements GeneratorAccess, AutoCloseable {
             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/world/level/block/BlockPlant.java b/src/main/java/net/minecraft/world/level/block/BlockPlant.java
index 33a5c5a4dc1478ab211dbb2e09df87570b06644f..81fbdda5e87b07259db206316cb4b423d9acdc3c 100644
--- a/src/main/java/net/minecraft/world/level/block/BlockPlant.java
+++ b/src/main/java/net/minecraft/world/level/block/BlockPlant.java
@@ -23,7 +23,7 @@ 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/world/level/block/BlockTallPlant.java b/src/main/java/net/minecraft/world/level/block/BlockTallPlant.java
index ca22187625f7ac6c43b663fd4d66cbf0c943c655..7c34cc7c0b74a336d0f0e705deab6d0f86e2e5f8 100644
--- a/src/main/java/net/minecraft/world/level/block/BlockTallPlant.java
+++ b/src/main/java/net/minecraft/world/level/block/BlockTallPlant.java
@@ -83,7 +83,7 @@ public class BlockTallPlant extends BlockPlant {
 
     protected static void b(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