Inventory

@VitalInventory.Info(type = VitalInventory.Type.GENERIC_9X3, name = "My inventory")
public class MyInventory extends VitalInventory {
    @Override
    public void onUpdate() {
        // This item doesn’t do anything.
        setItem(0, new ItemStack(Material.STICK));
    }

    @Override
    public void onUpdate(Player player) {
        // This item can be clicked.
        setItem(1, new ItemStack(Material.COBBLESTONE), (e) -> {
            // Do something when this item is clicked.
            player.sendMessage("You have clicked the item in slot 1");
        });
    }
}