[15:41:19 ERROR]: Could not pass event BlockBreakEvent to DiamondOreCounter v1.0

org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:310) ~[spigot.jar:git-Spigot-44c59bf-b023c53]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.jav
a:62) ~[spigot.jar:git-Spigot-44c59bf-b023c53]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.j
ava:502) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.j
ava:487) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.PlayerInteractManager.breakBlock(PlayerI
nteractManager.java:286) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.PlayerInteractManager.a(PlayerInteractMa
nager.java:215) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java
:614) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.PacketPlayInBlockDig.a(SourceFile:40) [s
pigot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.PacketPlayInBlockDig.a(SourceFile:10) [s
pigot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:1
3) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [
?:1.8.0_31]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_31]
        at net.minecraft.server.v1_8_R3.SystemUtils.a(SystemUtils.java:19) [spig
ot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:7
18) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:3
67) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:6
57) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java
:560) [spigot.jar:git-Spigot-44c59bf-b023c53]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_31]
Caused by: java.lang.ClassCastException: org.bukkit.event.block.BlockBreakEvent
cannot be cast to org.bukkit.entity.Player
        at me.bukkit.mykey.DiamondListener.inhanditem(DiamondListener.java:29) ~
[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0
_31]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0
_31]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1
.8.0_31]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_31]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:306) ~[spigot.jar:git-Spigot-44c59bf-b023c53]
        ... 17 more
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