public class Common implements Listener {
    private final Inventory inv;

    public Common() {
        // Create a new inventory, with no owner (as this isn't a real inventory), a size of nine, called example
        inv = Bukkit.createInventory(null, 27, "Common");

        // Put the items into the inventory
        initializeItems();
    }

    // You can call this whenever you want to put the items in
    public void initializeItems() {
        inv.setItem(10, createGuiItem(Material.ENCHANTED_BOOK, ChatColor.translateAlternateColorCodes('&', "&7XP Give")));
        inv.setItem(12, createGuiItem(Material.ENCHANTED_BOOK, ChatColor.translateAlternateColorCodes('&',"&7JumpBoost"), "UWU"));
        inv.setItem(14, createGuiItem(Material.ENCHANTED_BOOK, ChatColor.translateAlternateColorCodes('&',"&7Haste"), "UWU"));
        inv.setItem(16, createGuiItem(Material.ENCHANTED_BOOK, ChatColor.translateAlternateColorCodes('&',"&7Speed"), "UWU"));
    }

    // Nice little method to create a gui item with a custom name, and description
    protected ItemStack createGuiItem(final Material material, final String name, final String... lore) {
        final ItemStack item = new ItemStack(material, 1);
        final ItemMeta meta = item.getItemMeta();

        // Set the name of the item
        meta.setDisplayName(name);

        // Set the lore of the item
        meta.setLore(Arrays.asList(lore));

        item.setItemMeta(meta);

        return item;
    }

    // You can open the inventory with this
    public void openInventory(final HumanEntity ent) {
        ent.openInventory(inv);
    }

    // Check for clicks on items
    @EventHandler
    public void onInventoryClick(final InventoryClickEvent e) {
        if (!e.getInventory().equals(inv)) return;

        e.setCancelled(true);

        final ItemStack clickedItem = e.getCurrentItem();

        // verify current item is not null
        if (clickedItem == null) return;

        final Player p = (Player) e.getWhoClicked();

        if(e.getRawSlot() == 10) {
            //Click here
        }

    }

    // Cancel dragging in our inventory
    @EventHandler
    public void onInventoryClick(final InventoryDragEvent e) {
        if (e.getInventory().equals(inv)) {
            e.setCancelled(true);
        }
    }
}