[18:34:05 INFO]: UltraDev issued server command: /shardbooktesting TestBook 50 0 DIAMOND_PICKAXE JACKHAMMER
[18:34:05 ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'shardbooktesting' in plugin PickaxeLevel v[1.0.0]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[patched_1.12.2.jar:git-Paper-1618]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:152) ~[patched_1.12.2.jar:git-Paper-1618]
        at org.bukkit.craftbukkit.v1_12_R1.CraftServer.dispatchCommand(CraftServer.java:685) ~[patched_1.12.2.jar:git-Paper-1618]
        at net.minecraft.server.v1_12_R1.PlayerConnection.handleCommand(PlayerConnection.java:1492) ~[patched_1.12.2.jar:git-Paper-1618]
        at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1297) ~[patched_1.12.2.jar:git-Paper-1618]
        at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:45) ~[patched_1.12.2.jar:git-Paper-1618]
        at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:5) ~[patched_1.12.2.jar:git-Paper-1618]
        at net.minecraft.server.v1_12_R1.PlayerConnectionUtils.lambda$ensureMainThread$0(PlayerConnectionUtils.java:14) ~[patched_1.12.2.jar:git-Paper-1618]
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[?:1.8.0_242]
        at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_242]
        at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) ~[patched_1.12.2.jar:git-Paper-1618]
        at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:850) ~[patched_1.12.2.jar:git-Paper-1618]
        at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:423) ~[patched_1.12.2.jar:git-Paper-1618]
        at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:774) ~[patched_1.12.2.jar:git-Paper-1618]
        at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:666) ~[patched_1.12.2.jar:git-Paper-1618]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_242]
Caused by: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
        at java.lang.String.substring(String.java:1967) ~[?:1.8.0_242]
        at com.vk2gpz.enchantmentbook.d.a(d.java:217) ~[?:?]
        at com.vk2gpz.enchantmentbook.EnchantmentBook.getTEBook(EnchantmentBook.java:84) ~[?:?]
        at me.zach.shards.ShardbookCommand.execute(ShardbookCommand.java:37) ~[?:?]
        at me.zach.shards.ShardbookCommand.onCommand(ShardbookCommand.java:25) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[patched_1.12.2.jar:git-Paper-1618]
        ... 15 more