Cross-server nicknames using HubAPI

NicknameVault

package com.castawaydev.nicknamevault;
 
import com.castawaydev.hubapi.HubAPI;
import com.google.common.collect.Sets;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
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.PlayerJoinEvent;
import org.bukkit.plugin.PluginManager;
import org.bukkit.plugin.java.JavaPlugin;
 
 
public class NicknameVault extends JavaPlugin implements Listener
{
    
    private final Set<String> fetch = Sets.newHashSet("nickname");
  
    public void onLoad() 
    {
        Map<String, String> nicks = new HashMap();
        nicks.put("nickname", "VARCHAR(16)");
        HubAPI.register("nicknames", nicks);
    }
  
 
    public void onEnable()
    {
        Bukkit.getPluginManager().registerEvents(this, this);
    }
  
 
    public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args)
    {
        if (args.length < 1)
        {
            sender.sendMessage("Usage: /xnick [player] <nick>");
            return true;
        }
        if ((args.length < 2) && (!(sender instanceof Player)))
        {
            sender.sendMessage("Console cannot have a nickname >:3");
            return true;
        }
        if (((args.length == 2) && (!sender.hasPermission("xnick.other"))) || ((args.length == 1) && (!sender.hasPermission("xnick.self"))))
        {
            sender.sendMessage("Insufficient permissions!");
            return true;
        }
    
        String player;
        String nick;
        if (args.length == 2)
        {
            String player = args[0];
            nick = args[1];
        }
        else
        {
            player = sender.getName();
            nick = args[0];
        }
    
        if (nick.length() >= 16)
        {
            sender.sendMessage("Nickname is too long! (should be 16 or less)");
            return true;
        }
    
        Player p = Bukkit.getPlayer(nick);
        if (p != null)
        {
            p.setDisplayName(ChatColor.translateAlternateColorCodes('&', nick));
        }
        final Map<String, Object> n = new HashMap<String, Object>();
        n.put("nickname", nick);
        new BukkitRunnable()
        {
            @Override
            public void run()
            {
                HubAPI.set("nickname", p.getName(), n);
            }
        }.runTaskAsynchronously(this);
        return true;
    }
  
    @EventHandler
    public void onJoin(PlayerJoinEvent event)
    {
        Player player = event.getPlayer();
        new BukkitRunnable()
        {
            @Override
            public void run()
            {
                Response r = HubAPI.set("nickname", p.getName(), NicknameVault.this.fetch);
                if(r.wasSuccessful())
                {
                    String nick = r.get("nickname", "");
                    if(nick.isEmpty())
                        return;
                    p.setDisplayName(ChatColor.translateAlternateColorCodes('&', nick));
                }
            }
        }.runTaskAsynchronously(this);
    }
}