private function generateBundleBundleClass()
    {
        // add optional bundles if defined by parameter.
        if ($this->bundleAdditions !== null) {
            $this->bundleBundleGenerator->setAdditions($this->bundleAdditions);
        } else {
            $this->bundleBundleGenerator->setAdditions([]);
        }

        $this->bundleBundleGenerator->generate(
            $this->bundleBundleList,
            $this->bundleBundleNamespace,
            $this->bundleBundleClassname,
            $this->bundleBundleClassfile
        );
    }