Hỏi đáp Power

package me.adairh.ws;

import java.util.HashMap;
import java.util.UUID;

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.PlayerJoinEvent;
import org.bukkit.plugin.java.JavaPlugin;

public class main extends JavaPlugin implements Listener{
    public void onEnable(){
        getServer().getPluginManager().registerEvents(this, this);
    }
    HashMap<UUID, Integer> power = new HashMap <UUID, Integer>();
    @EventHandler
    public void onPlayerJoinEvent(PlayerJoinEvent e) {
        Player p = e.getPlayer();
      if(!p.hasPlayedBefore()) {
        
              power.put(p.getUniqueId(), 100);
              
      }
    }
    @Override
     public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args)
      {
        getCommand("ws").setExecutor(this);
        if (label.equalsIgnoreCase("ws"))
        {
          if (args.length >= 1) {
            if (args[0].equalsIgnoreCase("Power"))
            {
              if (sender.hasPermission("ws.use"))
              {
                sender.sendMessage(ChatColor.translateAlternateColorCodes('&',  "&aNăng lượng của bạn &6&l" + power.get(power)));
              }
              else
              {
                sender.sendMessage(
                  ChatColor.translateAlternateColorCodes('&', "&aYou don't"
                          + " have enough permissions to use this command"));
              }
            }
            
          }
          return false;
        }
        return false;
      }
}