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/BlockPlant.java b/src/main/java/net/minecraft/server/BlockPlant.java
index 47e370667926e59f036be3f2befe8820668cf892..a830305f0e334ad87e6b9ed94230ff611d997d7e 100644
--- a/src/main/java/net/minecraft/server/BlockPlant.java
+++ b/src/main/java/net/minecraft/server/BlockPlant.java
@@ -14,7 +14,7 @@ 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 48eb9c8a68d45c88c7a42e8e400446a374fb4fc9..2c8d49501664862559ed8974b4821bdd36fabebf 100644
--- a/src/main/java/net/minecraft/server/BlockTallPlant.java
+++ b/src/main/java/net/minecraft/server/BlockTallPlant.java
@@ -67,7 +67,7 @@ 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
diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 38b0863bf470682b9afaab016c5c41af65800e5d..575b4e670810b0be51067ba3e4c838e547a1f1dc 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -1175,6 +1175,7 @@ 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/World.java b/src/main/java/net/minecraft/server/World.java
index 7c6127739f1d88ee0dc411db5fcaa37d7fff36f7..5ce86030a71c181c4c28b8934be4fa8c7eafc299 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -406,7 +406,7 @@ 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);
 
@@ -508,7 +508,7 @@ 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/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
index a7b78b317dc70816fb0b23989bebe30a300ed561..7a1f6d446fb62b0aa72212b44899606c8ec99b55 100644
--- a/src/main/java/net/minecraft/server/WorldServer.java
+++ b/src/main/java/net/minecraft/server/WorldServer.java
@@ -87,6 +87,7 @@ public class WorldServer extends World implements GeneratorAccessSeed {
     private int tickPosition;
     public final Convertable.ConversionSession convertable;
     public final UUID uuid;
+    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);