"sender cannot be resolved to a variable"- noob question

I just starting out with plugin development.

I am following this tutorial:

I am getting an error that the "sender" variable can't be defined for some reason. As I said I have no idea what I'm doing so if someone could help me out in plain English that would be much appreciated.

Here's my source:

Code:java

package me.jay.myPlugin;
 
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 class Tutorial extends JavaPlugin {
 
    public void onEnable() {
        getLogger().info("It's on!");
    }
 
    public void onDisable() {
        getLogger().info("It's off!");
    }
 
    public boolean onCommand(CommandSender server, Command cmd, String label, String[] args){
            if(sender instanceof Player) {
                Player player = (Player) sender;
                if(cmd.getName().equalsIgnoreCase("Hello")) {
                    player.sendMessage(ChatColor.AQUA + "Hello World!");
                }
 
    }
}

 

Jayteescout
Nooby mistake indeed, you mispelled sender in your onCommand.
You had it like this

Code:java

public boolean onCommand(CommandSender server, Command cmd, String label, String[] args){

Notice how it is (CommandSender server) it should be (CommandSender sender)
Do it like this

Code:java

public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args){
if(sender instanceof Player) {
Player player = (Player) sender;
if(cmd.getName().equalsIgnoreCase("Hello")) {
player.sendMessage(ChatColor.AQUA + "Hello World!");
}
 
}
}

 

Ah, thanks!

 

Are you using an IDE (Eclipse, netbeans, etc.)?

If not, I seriously suggest it. They pickup silly errors like this very easily!