code[22:32:41 ERROR]: Could not pass event PlayerJoinEvent to AttributeDemo v1.0-SNAPSHOT
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.PlayerList.onPlayerJoin(PlayerList.java:332) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.PlayerList.a(PlayerList.java:158) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.LoginListener.b(LoginListener.java:144) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.LoginListener.c(LoginListener.java:54) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.NetworkManager.a(NetworkManager.java:232) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.ServerConnection.c(ServerConnection.java:141) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.MinecraftServer.D(MinecraftServer.java:820) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.DedicatedServer.D(DedicatedServer.java:400) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.MinecraftServer.C(MinecraftServer.java:660) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.minecraft.server.v1_9_R1.MinecraftServer.run(MinecraftServer.java:559) [spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_72]
Caused by: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
at java.lang.AbstractStringBuilder.deleteCharAt(AbstractStringBuilder.java:797) ~[?:1.8.0_72]
at java.lang.StringBuilder.deleteCharAt(StringBuilder.java:253) ~[?:1.8.0_72]
at org.bukkit.craftbukkit.v1_9_R1.attribute.CraftAttributeMap.toMinecraft(CraftAttributeMap.java:32) ~[spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at org.bukkit.craftbukkit.v1_9_R1.attribute.CraftAttributeMap.getAttribute(CraftAttributeMap.java:20) ~[spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at org.bukkit.craftbukkit.v1_9_R1.entity.CraftLivingEntity.getAttribute(CraftLivingEntity.java:493) ~[spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
at net.md_5.AttributeDemo.playerJoin(AttributeDemo.java:28) ~[?:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_72]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_72]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_72]
at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_72]
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.9.jar:git-Spigot-1a196e1-6f032cd]
... 14 more
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