Configuration problem

I am getting this error when I try to enable my plugin (I did not get it before adding the configuration):

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Code:

2012-01-10 16:43:14 [SEVERE] Error occurred while enabling ExpBank v0.3 (Is it up to date?): null
java.lang.NullPointerException
	at me.hayden.expbank.ExpBank.onEnable(ExpBank.java:78)
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:228)
	at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:970)
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:280)
	at org.bukkit.craftbukkit.CraftServer.loadPlugin(CraftServer.java:186)
	at org.bukkit.craftbukkit.CraftServer.enablePlugins(CraftServer.java:169)
	at net.minecraft.server.MinecraftServer.t(MinecraftServer.java:348)
	at net.minecraft.server.MinecraftServer.a(MinecraftServer.java:335)
	at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:165)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:399)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:457)

Here is the configuration related stuff from my main class (made with this tutorial):

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Code:

	FileConfiguration ExpBankConfig;
	public double config_bankxcoord = 0;
	public double config_bankycoord = 64;
	public double config_bankzcoord = 0;
	public String config_bankworld = "world";

        @Override
	public void onEnable(){
	    ExpBankConfig.options().header("Set your Bank Location");
	    ExpBankConfig.addDefault("Bank Location.X", 0);
	    ExpBankConfig.addDefault("Bank Location.Y", 64);
	    ExpBankConfig.addDefault("Bank Location.Z", 0);
	    ExpBankConfig.options().copyDefaults(true);
	    saveConfig();
	    config_bankxcoord = (Double) ExpBankConfig.get("Bank Location.X");
	    config_bankycoord = (Double) ExpBankConfig.get("Bank Location.Y");
	    config_bankzcoord = (Double) ExpBankConfig.get("Bank Location.Z");
	}

 

what line is line 78?

 

What specifically is line 78?

Add this to your onEnable

Code:java

FileConfiguration ExpBankConfig = this.getConfig();

Because i do believe you never actually set what ExpBankConfig was referring to

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

I think I can guess where line 78 is - the first line inside onEnable().

You've declared your FileConfiguration object, but you haven't actually initialised it to anything. So it's null when you come to use it.

 

lol sorry yes @desht guessed right, I didn't know objects needed to be initialised, thanks everyone.
Edit: now I'm getting another error:

Code:

2012-01-10 17:10:34 [SEVERE] Error occurred while enabling ExpBank v0.3 (Is it up to date?): java.lang.Integer cannot be cast to java.lang.Double
java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Double
	at me.hayden.expbank.ExpBank.onEnable(ExpBank.java:84)
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:228)
	at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:970)
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:280)
	at org.bukkit.craftbukkit.CraftServer.loadPlugin(CraftServer.java:186)
	at org.bukkit.craftbukkit.CraftServer.enablePlugins(CraftServer.java:169)
	at net.minecraft.server.MinecraftServer.t(MinecraftServer.java:348)
	at net.minecraft.server.MinecraftServer.a(MinecraftServer.java:335)
	at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:165)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:399)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:457)

I'm always completely lost when I try to convert data types...

 

Code:

java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Double

at me.hayden.expbank.ExpBank.onEnable(ExpBank.java:84)

Check over the Int/Doubles you are using on this line?

 

there are no ints only doubles, so I dont know what the problem is.

 

Are you reading from the config, and something is being treated as INT in the config?

 

it apears that all entries in the config are objects not ints ot Doubles

BUMP

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Well, why are you tring to use doubles in the first place? Presumably your "bank" co-ordinates are those of a block (not an entity), so integers are all you need here. You've even supplied integers (0, 64, 0) for the co-ordinate defaults.

(You're getting the class cast exception because the FileConfiguration get() method is returning Integer objects to you, and those cannot be cast directly to Double).

 

Oh, thanks, I was being a bit (very) stupid. The Double thing is a remnant of an old failed attempt at doing something related.