public function getUserManager()
    {
        if ($this->userManager != null) {
            return $this->userManager;
        }

        $this->userManager = new UserManager($this->options, $this->getUserService(), $this->getContentTypeService(), $this->getUserGroupManager());

        if ($this->logger) {
            $this->userManager->setLogger($this->logger);
        }

        return $this->userManager;
    }