[00:43:30] [Server thread/ERROR]: Could not pass event BlockPlaceEvent to Main v1.0
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[Spigot.jar:git-Spigot-de459a2-51263e9]
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[Spigot.jar:git-Spigot-de459a2-51263e9]
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at org.bukkit.craftbukkit.v1_10_R1.event.CraftEventFactory.callBlockPlaceEvent(CraftEventFactory.java:146) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.ItemStack.placeItem(ItemStack.java:162) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.PlayerInteractManager.a(PlayerInteractManager.java:538) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.PlayerConnection.a(PlayerConnection.java:910) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.PacketPlayInUseItem.a(PacketPlayInUseItem.java:37) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.PacketPlayInUseItem.a(PacketPlayInUseItem.java:1) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.PlayerConnectionUtils$1.run(SourceFile:13) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_161]
	at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_161]
	at net.minecraft.server.v1_10_R1.SystemUtils.a(SourceFile:45) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.MinecraftServer.D(MinecraftServer.java:732) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.DedicatedServer.D(DedicatedServer.java:400) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.MinecraftServer.C(MinecraftServer.java:668) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at net.minecraft.server.v1_10_R1.MinecraftServer.run(MinecraftServer.java:567) [Spigot.jar:git-Spigot-de459a2-51263e9]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_161]
Caused by: java.lang.NullPointerException
	at com.warsz.dct.Main.onPlayerPlace(Main.java:23) ~[?:?]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_161]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_161]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_161]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_161]
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:302) ~[Spigot.jar:git-Spigot-de459a2-51263e9]
	... 18 more