org.bukkit.command.CommandException: Unhandled exception executing 'class customize' in class at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:148) ~[spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at org.bukkit.craftbukkit.v1_12_R1.CraftServer.dispatchCommand(CraftServer.java:648) ~[spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.PlayerConnection.handleCommand(PlayerConnection.java:1399) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1234) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:45) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:1) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_231] at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_231] at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:748) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:406) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:679) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:577) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_231] Caused by: java.lang.NullPointerException at com.sucy.skill.api.classes.RPGClass.getToolIcon(RPGClass.java:328) ~[?:?] at com.sucy.skill.gui.tool.GUITool.populateClassSelection(GUITool.java:421) ~[?:?] at com.sucy.skill.gui.tool.GUITool.populate(GUITool.java:354) ~[?:?] at com.sucy.skill.gui.tool.GUITool.setType(GUITool.java:316) ~[?:?] at com.sucy.skill.gui.tool.GUITool.open(GUITool.java:306) ~[?:?] at com.sucy.skill.cmd.CmdCustomize.execute(CmdCustomize.java:56) ~[?:?] at com.rit.sucy.commands.ConfigurableCommand.execute(ConfigurableCommand.java:550) ~[?:?] at com.rit.sucy.commands.ConfigurableCommand.execute(ConfigurableCommand.java:558) ~[?:?] at com.rit.sucy.commands.ConfigurableCommand.execute(ConfigurableCommand.java:516) ~[?:?] at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:141) ~[spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34] ... 14 more