Symfony/学说:can'；t登录数据库用户，这在security.yml中是不正确的

在过去的几天里，我一直在努力使用Symfony/Doctrine登录数据库用户，现在我很困（顺便说一句，我是Symfony的新手）。我使用in_memory提供程序（首先）登录，但现在我想使用数据库用户登录，我只是不知道出了什么问题。

我一遍又一遍地查看文件，我想我把一切都做好了。当我尝试登录时，它只会显示"无效凭据"。我不得不觉得这与安全有关。yml但我已经尽力了。下面是我的代码；

security.yml；

security:
providers:
    provider_users:
        entity:
            class: AppBundle:User
            property: username
encoders:
    AppBundle'Entity'User:
        algorithm: bcrypt
firewalls:
    dev:
        pattern: ^/(_(profiler|wdt)|css|images|js)/
        security: false
    main:
        pattern: ^/
        anonymous: ~
        provider: provider_users
        form_login:
            login_path: login
            check_path: login
access_control:
    - { path: ^/admin, roles: ROLE_ADMIN }

User.php；

<?php
// src/AppBundle/Entity/User.php
namespace AppBundle'Entity;
use Symfony'Component'Security'Core'User'UserInterface;
use Doctrine'ORM'Mapping as ORM;
/**
 * AppBundle'Entity'User
 *
 * @ORM'Table(name="users")
 * @ORM'Entity(repositoryClass="AppBundle'Entity'UserRepository")
 */
class User implements UserInterface, 'Serializable
{
    /**
     * @ORM'Column(name="id", type="integer")
     * @ORM'Id()
     * @ORM'GeneratedValue(strategy="AUTO")
     */
    private $id;
    /**
     * @ORM'Column(name="username", type="string", length=25, unique=true)
     */
    private $username;
    /**
     * @ORM'Column(name="salt", type="string", length=40)
     */
    private $salt;
    /**
     * @ORM'Column(name="password", type="string", length=40)
     */
    private $password;
    /**
     * @ORM'Column(name="email", type="string", length=60, unique=true)
     */
    private $email;
    /**
     * @ORM'Column(name="roles", type="string")
     */
    private $roles;
    /**
     * @ORM'Column(name="is_active", type="boolean")
     */
    private $isActive;
    public function __construct()
    {
        $this->isActive = true;
        $this->salt = base_convert(sha1(uniqid(mt_rand(), true)), 16, 36);
    }
    public function eraseCredentials()
    {
        //
    }
    /** @see 'Serializable::serialize() */
    public function serialize()
    {
        return serialize(array(
            $this->id,
            $this->username,
            $this->password,
        ));
    }
    /** @see 'Serializable::unserialize() */
    public function unserialize($serialized)
    {
        list (
            $this->id,
            $this->username,
            $this->password,
        ) = unserialize($serialized);
    }
    /**
     * 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 salt
     *
     * @param string $salt
     *
     * @return User
     */
    public function setSalt($salt)
    {
        $this->salt = $salt;
        return $this;
    }
    /**
     * Get salt
     *
     * @return string
     */
    public function getSalt()
    {
        return $this->salt;
    }
    /**
     * Set password
     *
     * @param string $password
     *
     * @return User
     */
    public function setPassword($password)
    {
        $this->password = $password;
        return $this;
    }
    /**
     * Get password
     *
     * @return string
     */
    public function getPassword()
    {
        return $this->password;
    }
    /**
     * Set email
     *
     * @param string $email
     *
     * @return User
     */
    public function setEmail($email)
    {
        $this->email = $email;
        return $this;
    }
    /**
     * Get email
     *
     * @return string
     */
    public function getEmail()
    {
        return $this->email;
    }
    /**
     * Set roles
     *
     * @param string $roles
     *
     * @return User
     */
    public function setRoles($roles)
    {
        $this->roles = json_encode($roles);
        return $this;
    }
    /**
     * Get roles
     *
     * @return string[]
     */
    public function getRoles()
    {
        return json_decode($this->roles);
    }
    /**
     * Set isActive
     *
     * @param boolean $isActive
     *
     * @return User
     */
    public function setIsActive($isActive)
    {
        $this->isActive = $isActive;
        return $this;
    }
    /**
     * Get isActive
     *
     * @return boolean
     */
    public function getIsActive()
    {
        return $this->isActive;
    }
}

我还测试了是否可以使用getRepository（）->findAll（）"手动"获取用户，这看起来不错；

array (size=1)
0 => 
    object(AppBundle'Entity'User)[323]
      private 'id' => int 20
      private 'username' => string 'user' (length=4)
      private 'salt' => string 'mqshzqa9syok0kw8ss4cscc84k4k804' (length=31)
      private 'password' => string 'user1' (length=5)
      private 'email' => string 'user@localhost.com' (length=18)
      private 'roles' => string '' (length=0)
      private 'isActive' => boolean true
success!

有什么建议吗？提前感谢！