มีวิธีใดบ้างที่จะ $string = new class(); ได้อัตโนมัติใน class อื่นๆ

<?php

class A{
    public function a1(){
        echo 'a1;';
    }
}

class B{
    public $a;
    public function __construct(){
        $this->a = new A();
    }
    public function b1(){
        $this->a->a1();
    }
    public function b2(){
        $a =& $this->a; //ทำให้เรียกใช้ object a ได้สั้นขึ้น
        $a->a1();
    }
}

class C extends B{
    public function c1(){
        $this->a->a1();
    }
}

$c = new C();
$c->b1();
$c->b2();
$c->c1();

class dy_Registry
{
    public $userinfo;
    public $login;
    public $db;
    public $debug;
    public $var;
    public $config;
    public $lang;
    public $cookie;
    public $session;
    public $forum_cache;
    public $module_cache;
    public $style_cache;
    public $cms_cache;
    public $ip_address;
    public $host_name;
    
    public function __construct()
    {
        $this->var =& new dy_Input;
        
        $this->cookie =& new dy_Cookie(COOKIE_PREFIX);
        
        $this->session =& new dy_Session(SESSION_PREFIX);
        
        $this->login =& new dy_Login;
        
		//------------------
		// GET USER IPADDRS
		//------------------
		preg_match( "/^([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})$/", $this->var->my_get_env('REMOTE_ADDR'), $match );
		$this->ip_address = $match[1].'.'.$match[2].'.'.$match[3].'.'.$match[4];

		if ( $this->ip_address == '...' )
		{
			echo "ไม่สามารถทราบหมายเลขไอพีของคุณได้";
			exit;
		}
        
        $this->host_name = gethostbyaddr($this->ip_address);
    }

class dy_Login
{
	
	public function __construct()
	{
	}
	
	private function insertLogin($USERID, $USERNAME, $COOKIE = '')
	{
		global $dyclass;

		$LOGINCODE = substr($USERNAME,0,5) . "_" . date("d-m-y_His") . "_" . rand(1111111,9999999);

        $dyclass->session->set('USERLOGINCODE', $LOGINCODE);
	
		if ( $COOKIE !== FALSE )
		{
			$timeArray = array(0 => 365, 1 => 7, 2 => 30, 3 => 90, 4 => 180);
			
			if ( $COOKIE > -1 && $COOKIE <= 4 )
			{
                $dyclass->cookie->set('USERLOGINCODE', $LOGINCODE, TIME_NOW + 86400 * $timeArray[$COOKIE] );
			}
		}
	
        $dyclass->db->query_insert('user_login',
                                        array(
                                            'user_id'       =>  $USERID, 
                                            'login_code'    =>  $LOGINCODE, 
                                            'login_ip'      =>  $dyclass->ip_address,
                                            'login_host'    =>  $this->host_name
                                            )
                                    );
        $dyclass->db->query_update('user', 
                                        array(
                                            'user_last_login'   =>  date(DATETIME_FORMAT), 
                                            'user_total_login'  =>  'user_total_login+1',
                                            'user_login_status' =>  1
                                            ), 
                                            "user_id = $USERID"
                                            );
	}
	
	public function getLogin($USERNAME, $PASSWORD, $COOKIE)
	{
		global $dyclass;

		$sql = $dyclass->db->query_fetch('user', 'user_id, user_name', 
                                        'user_name = "' . $db->escape($USERNAME) . '"
                                        AND user_password = "' . md5($db->escape($PASSWORD)) . '"'
                                        );
	
		if ( $dyclass->db->num_rows($sql) == 1 )
		{
            $row = $dyclass->db->fetch_array($sql);
			$this->insertLogin($row['user_id'], $row['user_name'], $COOKIE);
		}
		return $this->getUserInfo();
	}
    
    
	public function getUserInfo()
    {
        global $dyclass;
        
        if ( $dyclass->session->get('USERLOGINCODE') )
        {
            return $this->getUser($dyclass->session->get('USERLOGINCODE'));
        }
        else if ( $dyclass->cookie->get('USERLOGINCODE') )
        {
            return $this->getUser($dyclass->cookie->get('USERLOGINCODE'));
        }
        return $this->getGuest();
    }
	
	private function getUser($LOGINCODE)
	{
		global $dyclass;

		$SQL	= $db->query("SELECT uID 
								FROM " . $db->pre ."ulogin 
								WHERE uLoginCode = '{$LOGINCODE}'
								");
		
		if ( $db->numrows($SQL) == 1 )
		{	
		    $uLogin = $db->fetch_array($SQL);
		    
		    $uID	=	$uLogin['uID'];

			$SQL2 = $db->query("SELECT * FROM ". $db->pre ."user, ugroup
		         		 		WHERE uID=". $uID ."
				  				AND user.uGroupID=ugroup.uGroupID");
	
			if ( $db->numrows($SQL2) == 1 )
			{
				return $db->fetch_array($SQL2);
			}
			return $this->getGuest();
		}
		return $this->getGuest();
	}

	private function getGuest()
	{
		global $dyclass;

		$sql = $dyclass->db->query_fetch("user_group",'','usergroup_id = 8');

		if ( $dyclass->db->num_rows($sql) == 1 )
		{
			$row = $dyclass->db->fetch_array($sql);
            $row['style_id'] = DEFAULT_STYLE_ID;
            return $row;
		}
		return false;
	}
	
	public function logOut($USERID, $uLoginCode)
	{
		...
	}
}

class email extends PHPMailer{
   function send($email,$msg){
         $this->IsSMTP();
         //...
   }   
}