[12:48:37 ERROR]: Could not pass event PlayerCommandPreprocessEvent to Minecraft
Market v1.7
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:427) ~[spigot.jar:git-Spigot-1223]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.jav
a:62) ~[spigot.jar:git-Spigot-1223]
        at org.bukkit.plugin.TimedRegisteredListener.callEvent(TimedRegisteredLi
stener.java:30) ~[spigot.jar:git-Spigot-1223]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.j
ava:482) [spigot.jar:git-Spigot-1223]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.j
ava:467) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.PlayerConnection.handleCommand(PlayerCon
nection.java:926) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java
:815) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.PacketPlayInChat.a(PacketPlayInChat.java
:28) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.PacketPlayInChat.handle(PacketPlayInChat
.java:65) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:147
) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.ServerConnection.c(SourceFile:134) [spig
ot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:6
57) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:2
73) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:5
40) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java
:446) [spigot.jar:git-Spigot-1223]
        at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:6
17) [spigot.jar:git-Spigot-1223]
Caused by: java.lang.NullPointerException
        at org.bukkit.craftbukkit.v1_7_R1.entity.CraftHumanEntity.openInventory(
CraftHumanEntity.java:185) ~[spigot.jar:git-Spigot-1223]
        at com.minecraftmarket.gui.Gui.showGui(Gui.java:44) ~[?:?]
        at com.minecraftmarket.Commands.onStoreCommand(Commands.java:41) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0
_17]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.7.0
_17]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1
.7.0_17]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.7.0_17]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:425) ~[spigot.jar:git-Spigot-1223]
        ... 15 more
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