Mailbox::findBy

static function findBy($id, $email): ?Mailbox
{
	$instance = null;

	if ($id > 0)
	{
		if ($mailbox = MailMailboxTable::getUserMailbox($id))
		{
			$instance = static::createInstance($mailbox['ID'], false);
		}
	}

	if (!empty($email) && empty($instance))
	{
		$instance = static::getForUserByEmail($email);
	}

	if (!empty($instance))
	{
		return $instance;
	}

	return null;
}