public function verify()
    {
        if (is_null($this->verified)) {
            try {
                $this->verified = (bool) $this->verifyEnvironment();
                if (!$this->verified) {
                    throw new Exception\EnvironmentException("The adapter did not properly verify.");
                }
            } catch (\Exception $e) {
                $this->verificationError = $e->getMessage();
                $this->verified = false;
            }
        }

        return $this->verified;
    }