Doctrine persist（）无声地失败

Question

<?php // test.php
 require 'bootstrap.php';
 use \Acme\Doctrine as DoctrineUser;

 $newUserName = $_POST['username'];

 $user = new DoctrineUser\User;
 $user->setName($newUserName);

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

 echo "Created user with ID " . $user->getId() . "\n";
?>

没有任何内容被回显或插入数据库？我的类/对象正确实例化：

Doctrine\Common\Util\Debug::dump($user);

object(stdClass)[47]
public '__CLASS__' => string 'Acme\Doctrine\User' (length=17)
public 'id' => null
public 'name' => string 'cookie' (length=6)
public 'email' => null
public 'address1' => null

Doctrine\Common\Util\Debug::dump($entityManager);

object(stdClass)[47]
public '__CLASS__' => string 'Doctrine\ORM\EntityManager' (length=26)
public 'config' => 
object(stdClass)[58]
  public '__CLASS__' => string 'Doctrine\ORM\Configuration' (length=26)
  public '_attributes' => string 'Array(10)' (length=9)
public 'conn' => 
object(stdClass)[60]
  public '__CLASS__' => string 'Doctrine\DBAL\Connection' (length=24)
  public '_conn' => string 'Doctrine\DBAL\Driver\PDOConnection' (length=34)
...

目录结构：

/test.php
/src
  /Acme
     /Doctrine
         /User.php
/composer.json                         
/bootstrap.php  

我的服务器日志没有报告，权限似乎都没问题。有什么想法吗？

继承我的User实体：

<?php

 namespace Acme\Doctrine;

/**
 * @Entity(repositoryClass="UserRepository") @Table(name="users")
 */
class User
{
    /**
    * @Id @GeneratedValue @Column(type="integer")
    * @var int
    **/
   protected $id;

   /**
    * @Column(type="string")
    * @var string
    **/
   protected $name;
   /**
    * @Column(type="string")
    * @var string
    **/
   protected $email;
   /**
    * @Column(type="string")
    * @var string
    **/
   protected $address1;


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

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

   function getEmail() {
       return $this->email;
   }

   function getAddress1() {
       return $this->address1;
   }

   function setId($id) {
       $this->id = $id;
   }

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

   function setEmail($email) {
       $this->email = $email;
   }

   function setAddress1($address1) {
       $this->address1 = $address1;
   }



}

以上内容位于/src/Acme/Doctrine