Bukkit

hey sorry to bother i just want to help you out by fixing problems.
i got hurt and came up with this error

8/28/2015 4:07:06 PM [SEVERE] Could not pass event EntityDamageByEntityEvent to HurtHealth v1.3
8/28/2015 4:07:06 PM org.bukkit.event.EventException
8/28/2015 4:07:06 PM     at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:06 PM     at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:06 PM     at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:06 PM     at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:06 PM     at org.bukkit.craftbukkit.v1_8_R3.event.CraftEventFactory.callEvent(CraftEventFactory.java:86) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:06 PM     at org.bukkit.craftbukkit.v1_8_R3.event.CraftEventFactory.callEntityDamageEvent(CraftEventFactory.java:539) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:06 PM     at org.bukkit.craftbukkit.v1_8_R3.event.CraftEventFactory.handleEntityDamageEvent(CraftEventFactory.java:452) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at org.bukkit.craftbukkit.v1_8_R3.event.CraftEventFactory.handleLivingEntityDamageEvent(CraftEventFactory.java:571) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.EntityLiving.d(EntityLiving.java:1101) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.EntityLiving.damageEntity(EntityLiving.java:742) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.EntityMonster.damageEntity(EntityMonster.java:42) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.EntityHuman.attack(EntityHuman.java:1001) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.EntityPlayer.attack(EntityPlayer.java:1063) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:1328) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.PacketPlayInUseEntity.a(SourceFile:52) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.PacketPlayInUseEntity.a(SourceFile:11) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_51]
8/28/2015 4:07:07 PM     at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_51]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.SystemUtils.a(SystemUtils.java:19) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:718) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:367) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:657) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:560) [Spigot.jar:git-Spigot-044d928-e8c6403]
8/28/2015 4:07:07 PM     at java.lang.Thread.run(Unknown Source) [?:1.8.0_51]
8/28/2015 4:07:07 PM Caused by: java.lang.NullPointerException
8/28/2015 4:07:07 PM     at com.playernguyen.api.HurtHealthAPI.getVar(HurtHealthAPI.java:80) ~[?:?]
8/28/2015 4:07:07 PM     at com.playernguyen.api.HurtHealthAPI.DisplayHealth(HurtHealthAPI.java:27) ~[?:?]
8/28/2015 4:07:07 PM     at com.playernguyen.listener.HurtHealthListener.onEntityHurt(HurtHealthListener.java:24) ~[?:?]
8/28/2015 4:07:07 PM     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_51]
8/28/2015 4:07:07 PM     at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_51]
8/28/2015 4:07:07 PM     at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_51]
8/28/2015 4:07:07 PM     at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_51]
8/28/2015 4:07:07 PM     at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[Spigot.jar:git-Spigot-044d928-e8c6403]