Trying to make a config to have people change a message

This might be a noob question but how do I make it so users can edit the message that would pop up when you type in a command because I have this...

Code:

this.getConfig().options().copyDefaults(true);
this.saveConfig();

on the Enable(){ but I made a separate class for the command and I was wondering how I would change the message including the color codes in here...

Code:

public boolean onCommand(CommandSender sender, Command cmd, String Commandlabel, String[] args){
    String command = cmd.getName();
    Player player = (Player) sender;
    if(command.equalsIgnoreCase("offduty") && (sender.hasPermission(this.plugin.duty) || sender.isOp())){
        player.getInventory().clear();
        sender.getServer().broadcastMessage(ChatColor.RED + "[Guard Notice] " + ChatColor.GREEN + "--- " + ChatColor.BLUE + sender.getName() + ChatColor.GREEN + " is no longer on Duty! ---");
        player.getInventory().setHelmet(null);
        player.getInventory().setChestplate(null);
        player.getInventory().setLeggings(null);
        player.getInventory().setBoots(null);
    }else{
        sender.sendMessage(ChatColor.DARK_RED + "You do not have access to that command.");
    }
    return false;
    }
}

because when I try to insert getConfig() into this it underlines it in red.

 

make a constructor in the class.

First:

Code:

public <Plugin_Name> plugin;

then:

Code:

public CLASSNAME(PLUGINNAME plugin){
    this.plugin = plugin;
}

Finally do:

Code:

plugin.getConfig().getString("String");

 

Okay thank you I just figured the rest out.