Solved Error on getting List size()

Hello,

My plugin gives me the following error:

Code:

ava.lang.NullPointerException
    at me.matthijs110.sgmc.Listeners.PlayerInteract.<init>(PlayerInteract.java:38) ~[?:?]
    at me.matthijs110.sgmc.Main.registerListeners(Main.java:59) ~[?:?]
    at me.matthijs110.sgmc.Main.onEnable(Main.java:40) ~[?:?]
    at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:321) ~[spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:340) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:405) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at com.jadeningle.PluginManager.Utils.Control.enablePlugin(Control.java:79) [PluginManager-Reloaded-1.0.0.jar:?]
    at com.jadeningle.PluginManager.pluginManagerCommand.reloadPluginCommand(pluginManagerCommand.java:228) [PluginManager-Reloaded-1.0.0.jar:?]
    at com.jadeningle.PluginManager.pluginManagerCommand.onCommand(pluginManagerCommand.java:63) [PluginManager-Reloaded-1.0.0.jar:?]
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:141) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchCommand(CraftServer.java:641) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchServerCommand(CraftServer.java:627) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at net.minecraft.server.v1_8_R3.DedicatedServer.aO(DedicatedServer.java:412) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:375) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:654) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:557) [spigot_server.jar:git-Spigot-5f38d38-18fbb24]
    at java.lang.Thread.run(Thread.java:745) [?:1.8.0_25]

I am trying to get a random string from the stringiest in config.yml

This is the List in my main class:

Code:

public List<String> r_commands = getConfig().getStringList("Commands");

This is the code in my PlayerInteract class:

Code:

Random rand = new Random();
    int choise = rand.nextInt(instance.r_commands.size()); // Line 38
    String cmd = instance.r_commands.get(choise);

What is causing the problem? I checked the size by printing it out. It says 2. So an empty List can't be the problem.

 

If the error is occuring there the only thing which could be null is the list. Try printing that into the console above line 38.

 

@AppleMen Do yourself a favor and initialize field values in the constructor (or the onEnable() in JavaPlugin)

 

That did the trick Thank you