A bug I can't squash...

Hello all!

This is my first time making a plugin and I am about to finish it! I have compiled it and made it into a jar. There is just one problem. I when I load it onto my plugin testing server, I get an error.

Error:

2013-12-04 08:59:11 [INFO] This server is running CraftBukkit version git-Bukkit-1.6.4-R2.0-b2918jnks (MC: 1.6.4) (Implementing API version 1.6.4-R2.0)
2013-12-04 08:59:11 [SEVERE] Could not load 'plugins/Lagtest.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.ClassNotFoundException: com.castlecraft1.BukkitProject1
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:184)
at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:305)
at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:230)
at org.bukkit.craftbukkit.v1_6_R3.CraftServer.loadPlugins(CraftServer.java:241)
at org.bukkit.craftbukkit.v1_6_R3.CraftServer.<init>(CraftServer.java:219)
at net.minecraft.server.v1_6_R3.PlayerList.<init>(PlayerList.java:56)
at net.minecraft.server.v1_6_R3.DedicatedPlayerList.<init>(SourceFile:11)
at net.minecraft.server.v1_6_R3.DedicatedServer.init(DedicatedServer.java:107)
at net.minecraft.server.v1_6_R3.MinecraftServer.run(MinecraftServer.java:393)
at net.minecraft.server.v1_6_R3.ThreadServerApplication.run(SourceFile:583)
Caused by: java.lang.ClassNotFoundException: com.castlecraft1.BukkitProject1
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at org.bukkit.plugin.java.PluginClassLoader.findClass0(PluginClassLoader.java:80)
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:53)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:270)
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:173)
... 9 more
I think it has something to do with the server thinking that there is no class file. The problem is, there is a class file.
Here is the source code:

Code:java

package com.castlecraft1.BukkitProject1;
 
import org.bukkit.ChatColor;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;
import org.bukkit.plugin.java.JavaPlugin;
 
public final class MainClass extends JavaPlugin{
 
    private static final String commandLabel = null;
 
    @Override
    public void onEnable(){
        getLogger().info("onEnable has been invoked!");}
 
    @Override
    public void onDisable() {
        getLogger().info("onDisable has been invoked!");}
 
        public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args){
            Player player = (Player) sender;
            if (commandLabel.equalsIgnoreCase("Lagtest")){
                player.sendMessage(ChatColor.GREEN + "Lag test complete.");
            }
            return false;
 
}}
 
 
 

Code:java

My plugin.ymlname: Lagtest
main: com.castlecraft1.BukkitProject1
version: 0.0.1
commands:
  Lagtest:
      description: Tests for lag
      usage: /Lagtest
      permission: test.lagtest
      permission-message: You don't have permission to use the command!
 

Thanks for any help!

- Mike1022

 

Change main in plugin.yml to this:
com.castlecraft1.BukkitProject1.MainClass

 

Ok now the plugin loaded. But now I have this problem when I try to do /lagtest:

Code:java

14:29:03 [SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'lagtest' in plugin Lagtest v0.0.1
at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46)
at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:192)
at org.bukkit.craftbukkit.v1_6_R3.CraftServer.dispatchCommand(CraftServer.java:528)
at net.minecraft.server.v1_6_R3.PlayerConnection.handleCommand(PlayerConnection.java:968)
at net.minecraft.server.v1_6_R3.PlayerConnection.chat(PlayerConnection.java:886)
at net.minecraft.server.v1_6_R3.PlayerConnection.a(PlayerConnection.java:837)
at net.minecraft.server.v1_6_R3.Packet3Chat.handle(SourceFile:49)
at net.minecraft.server.v1_6_R3.NetworkManager.b(NetworkManager.java:296)
at net.minecraft.server.v1_6_R3.PlayerConnection.e(PlayerConnection.java:116)
at net.minecraft.server.v1_6_R3.ServerConnection.b(SourceFile:37)
at net.minecraft.server.v1_6_R3.DedicatedServerConnection.b(SourceFile:30)
at net.minecraft.server.v1_6_R3.MinecraftServer.t(MinecraftServer.java:592)
at net.minecraft.server.v1_6_R3.DedicatedServer.t(DedicatedServer.java:227)
at net.minecraft.server.v1_6_R3.MinecraftServer.s(MinecraftServer.java:488)
at net.minecraft.server.v1_6_R3.MinecraftServer.run(MinecraftServer.java:421)
at net.minecraft.server.v1_6_R3.ThreadServerApplication.run(SourceFile:583)
Caused by: java.lang.NullPointerException
at com.castlecraft1.BukkitProject1.MainClass.onCommand(MainClass.java:23)
at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44)
... 15 more
 

 

Well just a little tip. Don't cast to a player without checking if they are a player first. That may be the problem. Also there is not commandLabel variable just use label or cmd.

 

Don't try to follow the tutorial word for word (using the variable commandLabel..) if you aren't going to consistently do so. You changed the method declaration to using label instead of commandLabel.

 

Sorry, I am fairly new to Java. I don't know what you mean by "Don't cast to a player without checking if they are a player first." Also, when I use cmd or label, it Eclipse gives me a syntax error.

 

Casting a object to another object example:

Code:java

Player player = (Player) sender;

You are casting player to sender. So what if the console used this command you would get an error. As for the label do:

Code:java

if(label.equalsIgnoreCase("what ever")) {
//Stuff
}

 

Ok, thanks for all your help! 1 more question, so when I do /Lagtest in-game. It says Lagtest complete, (Like it's supposed to.) but under that it says /Lagtest.

 

Probably because you enabled the usage in the plugin.yml

 

because you aren't checking any of the arguments.

Code:

//If command equals /Lagtest in-game
if(args[0].equalsIngoreCase("in-game")) {
    //Do stuff
}

 

The_Coder

Mike1022

You need to return true; under the bracket after you send the message

 

sgavster
This.

 

Mike1022 You should not check the commands label but the actual command its self with cmd.getName().