Solved NamespacedKey cannot be resolved to a type

I was trying to add a recipe, and i literally copied from the spigot website the code:

Code:

package org.---.utilites;

import org.---.commands.FlyCommand;
import org.---.commands.GameUICommand;
import org.---.commands.HelloCommand;
import org.---.commands.gamemode.Adventure;
import org.--.commands.gamemode.Creative;
import org.---.commands.gamemode.Spectator;
import org.---.commands.gamemode.Survival;
import org.---.listeners.InventoryClickListener;
import org.---.listeners.JoinListeners;
import org.---.ui.GamesUI;
import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.Material;
import org.bukkit.enchantments.Enchantment;
import org.bukkit.inventory.ItemStack;
import org.bukkit.inventory.ShapedRecipe;
import org.bukkit.inventory.meta.ItemMeta;
import org.bukkit.plugin.java.JavaPlugin;
[B]import org.bukkit.NamespacedKey[/B]

public class Main extends JavaPlugin
{
    @Override
    public void onEnable()
    {
        saveDefaultConfig();
        //commands
        new HelloCommand(this);
        new GameUICommand(this);
        new FlyCommand(this);
      
        //gamemodes
        new Creative(this);
        new Survival(this);
        new Adventure(this);
        new Spectator(this);
      
        //listeners
        new JoinListeners(this);
        new InventoryClickListener(this);
      
        //ui initializer
        GamesUI.initialaize();
      
        //recipe
        ItemStack item = new ItemStack(Material.DIAMOND_SWORD);

        ItemMeta meta = item.getItemMeta();

        meta.setDisplayName(ChatColor.GREEN + "Emerald Sword");

        item.setItemMeta(meta);

        item.addEnchantment(Enchantment.DAMAGE_ALL, 5);
[B]
        NamespacedKey key = new NamespacedKey(this, "emerald_sword");
[/B]
        ShapedRecipe recipe = new ShapedRecipe(key, item);

        recipe.shape(" E ", " E ", " S ");

        recipe.setIngredient('E', Material.EMERALD);
        recipe.setIngredient('S', Material.STICK);

        Bukkit.addRecipe(recipe);
    }
}

Here are the errors:


ok i just found out that namespacedkey is 1.12 and im on 1.8.9

but i dont know how to do it still[/I][/INDENT]

 

I did, but i already fixed this. Thanks for responding tho