private function getResourceFromParameter($prefix = '--unique-prefix')
    {
        $resource = null;
        $hasParameter = false;

        $val = $this->getParameterValue($prefix);
        if ($val) {
            $hasParameter = true;
            $resource = $this->getResource($val);
            if (!$resource->exists()) {
                $resource = null;
            }
        }

        return $hasParameter ? $resource : false;
    }