[Create Fake Player] #Spigot

code.java

// These two lines should be outside the npc spawn function for caching
HashMap<String, String> skins = new HashMap<>();
HashMap<String, String> signatures = new HashMap<>();

// This code was written inside an command, thats why (Player) commandSender
Player player = (Player) commandSender;
MinecraftServer server = ((CraftServer) Bukkit.getServer()).getServer();
WorldServer world = ((CraftWorld) player.getWorld()).getHandle();
Location loc = player.getLocation();
for (int x = loc.getBlockX() - 16; x < loc.getBlockX() + 16; x++) {
  for (int z = loc.getBlockZ() - 16; z < loc.getBlockZ() + 16; z++) {
    GameProfile profile = new GameProfile(UUID.randomUUID(), player.getName());
    if (skins.containsKey(player.getName())) {
      profile.getProperties().put("textures", new Property("textures", skins.get(player.getName()), signatures.get(player.getName())));
    } else {
      try {
        HttpsURLConnection connection = (HttpsURLConnection) new URL(String.format("https://sessionserver.mojang.com/session/minecraft/profile/%s?unsigned=false", UUIDTypeAdapter.fromUUID(player.getUniqueId()))).openConnection();
        if (connection.getResponseCode() == HttpsURLConnection.HTTP_OK) {
          String reply = new BufferedReader(new InputStreamReader(connection.getInputStream())).readLine();
          String skin = reply.split("\"value\":\"")[1].split("\"")[0];
          String signature = reply.split("\"signature\":\"")[1].split("\"")[0];
          skins.put(player.getName(), skin);
          signatures.put(player.getName(), signature);
          profile.getProperties().put("textures", new Property("textures", skin, signature));
        } else {
          System.out.println("Connection could not be opened (Response code " + connection.getResponseCode() + ", " + connection.getResponseMessage() + ")");
        }
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
    EntityPlayer npc = new EntityPlayer(server, world, profile, new PlayerInteractManager(world));
    Location spawn = player.getLocation();
    npc.setLocation(x, loc.getBlockY(), z, 0, 0);

    for (Player onlinePlayer : Bukkit.getServer().getOnlinePlayers()) {
      PlayerConnection connection = ((CraftPlayer) onlinePlayer).getHandle().playerConnection;
      connection.sendPacket(new PacketPlayOutPlayerInfo(PacketPlayOutPlayerInfo.EnumPlayerInfoAction.ADD_PLAYER, npc));
      connection.sendPacket(new PacketPlayOutNamedEntitySpawn(npc));
    }
  }
}

ArrayList has a method called put ?
I thought more this is a HashMap, because the HashMap Class has a put method, but I just asked to be sure.

Of course its an hashmap, i'm just lost xD

Ok, that makes more sense
Anyways thanks xD