Null in command

Hello guys!

Hello people! He writes plug , but unfortunately it throws me an error after entering the command.

Here you have command code:

Code:

import org.bukkit.command.Command;
import org.bukkit.command.CommandExecutor;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;

import com.marosking.castlemod.main.CastlePlugin;

public class CreateCommand implements CommandExecutor {

    CastlePlugin plugin;

    public CreateCommand(CastlePlugin plugin) {
        this.plugin = plugin;
        this.plugin.getCommand("create").setExecutor(this);
    }

    @Override
    public boolean onCommand(CommandSender sender, Command command, String label, String[] args)
            throws NullPointerException {
        if (!(sender instanceof Player)) {
            sender.sendMessage("Musisz byc graczem, aby uzyc tej komendy!");
            return true;
        }

        Player player = (Player) sender;

        if ((!player.hasPermission("castle.commands.create")) && (!player.hasPermission("castle.admin"))) {
            player.sendMessage(this.plugin.fixColor("&4Blaod: &cNie masz uprawnien do wykonania tej komendy!"));
            return true;
        }

        if (args.length < 3 || args.length > 4) {
            player.sendMessage(
                    this.plugin.fixColor("&4Blad: &cPoprawne uzycie: /create <arena> <minPlayers> <maxPlayers>"));
            return true;
        }

        String arenaName = args[0];

        if (!arenaName.matches("[a-zA-Z]+")) {
            player.sendMessage(this.plugin.fixColor("&4Blad: &cNazwa areny moze skladac sie tylko z liter!"));
            return true;
        }

        int minPlayers = Integer.parseInt(args[1]);
        int maxPlayers = Integer.parseInt(args[2]);

        this.plugin.castleArenaManager.getManager().createArena(arenaName, minPlayers, maxPlayers);
        player.sendMessage(this.plugin.fixColor("&cArena o nazwie &4" + arenaName + " &czostala poprawnie utworzona!"));
        return true;
    }

}

Here you also have the functions of the creation of the arena:

Code:

public void createArena(String arenaName, int minPlayers, int maxPlayers) {
        CastleArena castleArena = new CastleArena(arenaName, minPlayers, maxPlayers);

        this.plugin.getConfigFile().set("arenas." + arenaName, null);
        this.plugin.getConfigFile().set("arenas." + arenaName + ".minPlayers", minPlayers);
        this.plugin.getConfigFile().set("arenas." + arenaName + ".maxPlayers", maxPlayers);
        this.plugin.saveConfig();

        this.castleArenas.put(arenaName, castleArena);
    }

And here you have code errors how when you type the command:

Code:

[06:02:46] [Server thread/ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'stworz' in plugin CastleMod v0.1
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[Spigot.jar:git-Spigot-044d928-e8c6403]
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:141) ~[Spigot.jar:git-Spigot-044d928-e8c6403]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchCommand(CraftServer.java:642) ~[Spigot.jar:git-Spigot-044d928-e8c6403]
    at net.minecraft.server.v1_8_R3.PlayerConnection.handleCommand(PlayerConnection.java:1135) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:970) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:45) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:1) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_101]
    at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_101]
    at net.minecraft.server.v1_8_R3.SystemUtils.a(SystemUtils.java:19) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:718) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:367) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:657) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:560) [Spigot.jar:git-Spigot-044d928-e8c6403]
    at java.lang.Thread.run(Thread.java:745) [?:1.8.0_101]
Caused by: java.lang.NullPointerException
    at com.marosking.castlemod.main.commands.CreateCommand.onCommand(CreateCommand.java:50) ~[?:?]
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[Spigot.jar:git-Spigot-044d928-e8c6403]
    ... 15 more

I really do not know what this can be null , please help!
P.S. Sorry for my English , but I'm Polish

 

@timtower
50 line is: this.plugin.castleArenaManager.getManager().createArena(arenaName, minPlayers, maxPlayers);
which here can be null?

 

What do you mean by "He writes plug"? Did you copy some of this code?

As @timtower mentioned, arena manager is null. This isn't your main class. Create a constructor to your main class, and use 'plugin' instead of 'this.plugin'. If it equals plugin, use it.

EDIT: I'm looking at the line numbers in my IDE.
If you have a good constructor, Then your class should take plugin.
If you pasted your ENTIRE CreateCommand class, then the line numbers tell me that line 50 is a return statement. Something in that if statement is null, assuming it's:

Code:

        this.plugin.castleArenaManager.getManager().createArena(arenaName, minPlayers, maxPlayers);

It could be castleArenamanager, or your constructor returning plugin as null (this.plugin = plugin)
Keep in mind that you don't need to use "this.plugin" if you have plugin equal "this.plugin".

Paste all of your main class, along with whatever classes this code uses.

EDIT 2: Also check for null on args[0]:

Code:

        String arenaName = args[0];

        if (!arenaName.matches("[a-zA-Z]+")) {
            player.sendMessage(this.plugin.fixColor("&4Blad: &cNazwa areny moze skladac sie tylko z liter!"));
            return true;
        }

EDIT 3: Don't blindly cast!!

Code:

        Player player = (Player) sender;

 

You should always use try catch instead of giving the Exception the JavaPlugin class wtf

And you forgot a bracket at the end of the onCommand method, didnt you?

 

No, he put it after the 'throw NullPointerException' line.
EDIT: I think so....

He's right though ^. Don't do that.

Code:

try{
    this.whatever();
} catch (Exception e) {
    e.printStackTrace();
}

 

lol sry, I am blind af