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 a0fda40b2b7b16b424ed08d3a63da8704317133c..4a9669422567983e2c3b3cee4f4ef945d4486d97 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -1517,6 +1517,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
 
         while (iterator.hasNext()) {
             ServerLevel worldserver = (ServerLevel) iterator.next();
+            worldserver.hasPhysicsEvent = org.bukkit.event.block.BlockPhysicsEvent.getHandlerList().getRegisteredListeners().length > 0; // Paper - BlockPhysicsEvent
 
             this.profiler.push(() -> {
                 String s = String.valueOf(worldserver);
diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
index 001cbed05de94cadd4862c38c414b5e039bff818..5b44a9e0b6d87e7caba54cb4e972099c1602393b 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -226,6 +226,7 @@ public class ServerLevel extends Level implements WorldGenLevel {
     // CraftBukkit start
     public final LevelStorageSource.LevelStorageAccess convertable;
     public final UUID uuid;
+    public boolean hasPhysicsEvent = true; // Paper - BlockPhysicsEvent
 
     public LevelChunk getChunkIfLoaded(int x, int z) {
         return this.chunkSource.getChunk(x, z, false);
diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
index 8ba4395670304647d62987952c6339d394140af6..33c9001970fe01bedd72f6ba4388b43ed9707fc8 100644
--- a/src/main/java/net/minecraft/world/level/Level.java
+++ b/src/main/java/net/minecraft/world/level/Level.java
@@ -490,7 +490,7 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
                 // CraftBukkit start
                 iblockdata1.updateIndirectNeighbourShapes(this, blockposition, k, j - 1); // Don't call an event for the old block to limit event spam
                 CraftWorld world = ((ServerLevel) this).getWorld();
-                if (world != null) {
+                if (world != null && ((ServerLevel)this).hasPhysicsEvent) { // Paper - BlockPhysicsEvent
                     BlockPhysicsEvent event = new BlockPhysicsEvent(world.getBlockAt(blockposition.getX(), blockposition.getY(), blockposition.getZ()), CraftBlockData.fromData(iblockdata));
                     this.getCraftServer().getPluginManager().callEvent(event);
 
diff --git a/src/main/java/net/minecraft/world/level/block/BushBlock.java b/src/main/java/net/minecraft/world/level/block/BushBlock.java
index 75109c79daa724340268438725bbf6d39b955691..a7b4b5600e3c889c69ac22294899713d50b5fe5c 100644
--- a/src/main/java/net/minecraft/world/level/block/BushBlock.java
+++ b/src/main/java/net/minecraft/world/level/block/BushBlock.java
@@ -28,7 +28,7 @@ public abstract class BushBlock extends Block {
     protected BlockState updateShape(BlockState state, Direction direction, BlockState neighborState, LevelAccessor world, BlockPos pos, BlockPos neighborPos) {
         // CraftBukkit start
         if (!state.canSurvive(world, pos)) {
-            if (!org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, pos).isCancelled()) {
+            if (!(world instanceof net.minecraft.server.level.ServerLevel && ((net.minecraft.server.level.ServerLevel) world).hasPhysicsEvent) || !org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, pos).isCancelled()) { // Paper
                 return Blocks.AIR.defaultBlockState();
             }
         }
diff --git a/src/main/java/net/minecraft/world/level/block/DoublePlantBlock.java b/src/main/java/net/minecraft/world/level/block/DoublePlantBlock.java
index cb76568cd1f97024c7a40328d9d72dd8a3e72e8b..7fdf744a2be55313cc75c1322f6534f55cf463f5 100644
--- a/src/main/java/net/minecraft/world/level/block/DoublePlantBlock.java
+++ b/src/main/java/net/minecraft/world/level/block/DoublePlantBlock.java
@@ -102,7 +102,7 @@ public class DoublePlantBlock extends BushBlock {
 
     protected static void preventDropFromBottomPart(Level world, BlockPos pos, BlockState state, Player player) {
         // CraftBukkit start
-        if (org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, pos).isCancelled()) {
+        if (((net.minecraft.server.level.ServerLevel)world).hasPhysicsEvent && org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, pos).isCancelled()) { // Paper
             return;
         }
         // CraftBukkit end