orm: Fatal error: Uncaught Doctrine\ORM\Mapping\MappingException

Here is generated entity code:

<?php



use Doctrine\ORM\Mapping as ORM;

/**
 * User
 *
 * @ORM\Table(name="database_a.user", indexes={@ORM\Index(name="address_id", columns={"address_id"})})
 * @ORM\Entity
 */
class User
{
    /**
     * @var integer
     *
     * @ORM\Column(name="id", type="integer", nullable=false)
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="IDENTITY")
     */
    private $id;

    /**
     * @var string
     *
     * @ORM\Column(name="username", type="text", length=65535, nullable=false)
     */
    private $username;

    /**
     * @var \Address
     *
     * @ORM\ManyToOne(targetEntity="Address")
     * @ORM\JoinColumns({
     *   @ORM\JoinColumn(name="address_id", referencedColumnName="id")
     * })
     */
    private $address;


    /**
     * Get id
     *
     * @return integer
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * Set username
     *
     * @param string $username
     *
     * @return User
     */
    public function setUsername($username)
    {
        $this->username = $username;

        return $this;
    }

    /**
     * Get username
     *
     * @return string
     */
    public function getUsername()
    {
        return $this->username;
    }

    /**
     * Set address
     *
     * @param \Address $address
     *
     * @return User
     */
    public function setAddress(\Address $address = null)
    {
        $this->address = $address;

        return $this;
    }

    /**
     * Get address
     *
     * @return \Address
     */
    public function getAddress()
    {
        return $this->address;
    }
}

<?php



use Doctrine\ORM\Mapping as ORM;

/**
 * Address
 *
 * @ORM\Table(name="database_b.address")
 * @ORM\Entity
 */
class Address
{
    /**
     * @var integer
     *
     * @ORM\Column(name="id", type="integer", nullable=false)
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="IDENTITY")
     */
    private $id;

    /**
     * @var string
     *
     * @ORM\Column(name="phone", type="text", length=65535, nullable=false)
     */
    private $phone;


    /**
     * Get id
     *
     * @return integer
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * Set phone
     *
     * @param string $phone
     *
     * @return Address
     */
    public function setPhone($phone)
    {
        $this->phone = $phone;

        return $this;
    }

    /**
     * Get phone
     *
     * @return string
     */
    public function getPhone()
    {
        return $this->phone;
    }
}

Here is my code I just made little change in generated entity and added database name before table name :

<?php
require_once "vendor/autoload.php";

use Doctrine\ORM\Tools\Setup;
use Doctrine\ORM\EntityManager;

$paths = array(__DIR__."/scr");
$isDevMode = false;

// the connection configuration
$dbParams = array(
    'driver'   => 'pdo_mysql',
    'user'     => 'xxxxx',
    'password' => 'xxxxx',
    'dbname'   => 'database_a',
);

$config = Setup::createAnnotationMetadataConfiguration($paths, $isDevMode);
$em = $entityManager = EntityManager::create($dbParams, $config);

require_once "Entities/User.php";
require_once "Entities/Address.php";

$data = $em->getRepository('User');
$datax = $data->findAll();

foreach($datax as $d) {
  echo '<pre>'; print_r($d);
}

error detail:

Fatal error: Uncaught Doctrine\ORM\Mapping\MappingException: Class "User" is not a valid entity or mapped super class. in D:\xampp\htdocs\docx\vendor\doctrine\orm\lib\Doctrine\ORM\Mapping\MappingException.php:346 Stack trace: #0 D:\xampp\htdocs\docx\vendor\doctrine\orm\lib\Doctrine\ORM\Mapping\Driver\AnnotationDriver.php(91): Doctrine\ORM\Mapping\MappingException::classIsNotAValidEntityOrMappedSuperClass('User') #1 D:\xampp\htdocs\docx\vendor\doctrine\orm\lib\Doctrine\ORM\Mapping\ClassMetadataFactory.php(151): Doctrine\ORM\Mapping\Driver\AnnotationDriver->loadMetadataForClass('User', Object(Doctrine\ORM\Mapping\ClassMetadata)) #2 D:\xampp\htdocs\docx\vendor\doctrine\common\lib\Doctrine\Common\Persistence\Mapping\AbstractClassMetadataFactory.php(332): Doctrine\ORM\Mapping\ClassMetadataFactory->doLoadMetadata(Object(Doctrine\ORM\Mapping\ClassMetadata), NULL, false, Array) #3 D:\xampp\htdocs\docx\vendor\doctrine\orm\lib\Doctrine\ORM\Mapping\ClassMetadataFactory.php(78): Doctrine\Common\Persistence\Mapping\AbstractClassMetada in D:\xampp\htdocs\docx\vendor\doctrine\orm\lib\Doctrine\ORM\Mapping\MappingException.php on line 346