Could not pass event PlayerInteractEvent to AssemblyLineFurn

30.05 07:10:41 [Server] INFO at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:425)
30.05 07:10:41 [Server] INFO at java.lang.reflect.Method.invoke(Unknown Source)
30.05 07:10:41 [Server] INFO at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
30.05 07:10:41 [Server] INFO at sun.reflect.GeneratedMethodAccessor227.invoke(Unknown Source)
30.05 07:10:41 [Server] INFO at com.almramc.assemblylinefurnace.AssemblyFurnace.onPlayerInteract(AssemblyFurnace.java:47)
30.05 07:10:41 [Server] INFO at com.almramc.assemblylinefurnace.WorkingFurnaceListener.addWorkingFurnace(WorkingFurnaceListener.java:75)
30.05 07:10:41 [Server] INFO at com.almramc.assemblylinefurnace.WorkingFurnaceListener.refreshInput(WorkingFurnaceListener.java:262)
30.05 07:10:41 [Server] INFO Caused by: java.lang.NullPointerException
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.ThreadServerApplication.run(SourceFile:573)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.MinecraftServer.run(MinecraftServer.java:410)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.MinecraftServer.q(MinecraftServer.java:477)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.DedicatedServer.r(DedicatedServer.java:226)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.MinecraftServer.r(MinecraftServer.java:581)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.DedicatedServerConnection.b(SourceFile:30)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.ServerConnection.b(SourceFile:35)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.PlayerConnection.d(PlayerConnection.java:109)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.NetworkManager.b(NetworkManager.java:292)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.Packet14BlockDig.handle(SourceFile:46)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.PlayerConnection.a(PlayerConnection.java:541)
30.05 07:10:41 [Server] INFO at net.minecraft.server.v1_5_R3.PlayerInteractManager.dig(PlayerInteractManager.java:108)
30.05 07:10:41 [Server] INFO at org.bukkit.craftbukkit.v1_5_R3.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:186)
30.05 07:10:41 [Server] INFO at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
30.05 07:10:41 [Server] INFO at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
30.05 07:10:41 [Server] INFO at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
30.05 07:10:41 [Server] INFO at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:427)
30.05 07:10:41 [Server] INFO org.bukkit.event.EventException
30.05 07:10:41 [Server] SEVERE Could not pass event PlayerInteractEvent to AssemblyLineFurnace v1.0