Doctrine Entity "Class not found"

I'm proceeding to Doctrine's Getting Started guide and stuck in the beginning because of "Class 'Product' not found in /var/www/test/product-create.php on line 6":

<?php
require_once 'bootstrap.php';

$newProductName = $argv[1];

>>>>> $product = new Product();
$product->setName($newProductName);

$entityManager->persist($product);
$entityManager->flush();

echo sprintf('Created Product with ID %d' . PHP_EOL, $product->getId());

As written in guide, I have the Product class under "./src" directory in my project.

Please, help me, because I want to start using Doctrine without Symfony and I can't move any further.

Here is my bootstrap.php:

<?php
use Doctrine\ORM\Tools\Setup;
use Doctrine\ORM\EntityManager;

use Symfony\Component\Yaml\Parser;

require 'vendor/autoload.php';

$yaml = new Parser();

$parameters = $yaml->parse(file_get_contents(__DIR__ . '/parameters.yml'));
$parameters = $parameters['parameters'];

$config = Setup::createAnnotationMetadataConfiguration(array(__DIR__ . '/src'), $parameters['debug']);

$conn = array
    (
        'host'      => $parameters['database_host'],
        'port'      => $parameters['database_port'],
        'driver'    => $parameters['database_driver'],
        'user'      => $parameters['database_user'],
        'password'  => $parameters['database_password'],
        'dbname'    => $parameters['database_name']
    );

$entityManager = EntityManager::create($conn, $config);

And this is my Product.php:

<?php
/**
 * @Entity
 * @Table (name="products")
 **/
class Product
{
    /**
     * @Id
     * @Column(type="integer") @GeneratedValue
     **/
    protected $id;

    /**
     * @Column(type="string")
     **/
    protected $name;

    public function getId()
    {
        return $this->id;
    }

    public function getName()
    {
        return $this->name;
    }

    public function setName($name)
    {
        $this->name = $name;
    }
}

Thank you all in advance!

I dont see where you include Product class. You need to write in the top of your file

require_once 'patch_to_your_class/Product.php';

or to use an autoloader for classes.