Créer des groupes (de chat) main class

package fr.src.gc;

import java.util.ArrayList;

import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.player.AsyncPlayerChatEvent;
import org.bukkit.event.player.PlayerJoinEvent;
import org.bukkit.plugin.PluginManager;
import org.bukkit.plugin.java.JavaPlugin;

public class Main extends JavaPlugin implements Listener{

    public void onEnable()
    {
        PluginManager pm = Bukkit.getServer().getPluginManager();
        pm.registerEvents(this, this);
    }

    public void onDisable()
    {

    }

    public GroupCommerce commerce = new GroupCommerce(ChatColor.GOLD, new ArrayList<Player>(), "Commerce");
    public GroupGeneral general = new GroupGeneral(ChatColor.GREEN, new ArrayList<Player>(), "General");

    @EventHandler
    public void Join(PlayerJoinEvent e)
    {
        Player p = e.getPlayer();

        general.AddPlayer(p);
        p.sendMessage(ChatColor.GREEN+"--- Vous êtes désormais dans le groupe Général ---");
    }

    @EventHandler
    public void Chat(AsyncPlayerChatEvent e)
    {
        Player localPlayer = e.getPlayer();


        for(Player group : commerce.getGroupPlayers())
        {
            if(commerce.getGroupPlayers().contains(localPlayer))
            {
                group.sendMessage(commerce.getGroupColor()+"[Commerce] "+ChatColor.WHITE+"<"+localPlayer.getDisplayName()+"> - "+commerce.getGroupColor()+e.getMessage());
            }
        }

            for(Player group : general.getGroupPlayers())
            {
                if(general.getGroupPlayers().contains(localPlayer))
                {
                    group.sendMessage(ChatColor.WHITE+"[General] <"+localPlayer.getDisplayName()+"> - "+e.getMessage());
                }
            }

            e.setCancelled(true);
    }

    public boolean onCommand(CommandSender sender, Command cmd, String label, String args[])
    {
        Player p = (Player) sender;

        if(cmd.getName().equalsIgnoreCase("join"))
        {
            if(args[0].equalsIgnoreCase("Commerce"))
            {
            general.RemovePlayer(p);
            commerce.AddPlayer(p);
            p.sendMessage(ChatColor.GOLD+"--- Vous êtes désormais dans le groupe Commerce ---");
            }
        }

        if(cmd.getName().equalsIgnoreCase("leave"))
        {
            if(args[0].equalsIgnoreCase("Commerce"))
            {
            commerce.RemovePlayer(p);
            general.AddPlayer(p);
            p.sendMessage(ChatColor.GREEN+"--- Vous êtes désormais dans le groupe Général ---");
            }
        }

        return true;
    }

}