public function generateXsd($viewHelperNamespace, $xsdNamespace)
    {
        if (substr($viewHelperNamespace, -1) !== '\\') {
            $viewHelperNamespace .= '\\';
        }

        $classNames = $this->getClassNamesInNamespace($viewHelperNamespace);
        if (count($classNames) === 0) {
            throw new Exception(sprintf('No ViewHelpers found in namespace "%s"', $viewHelperNamespace), 1330029328);
        }

        $xmlRootNode = new \SimpleXMLElement('<?xml version="1.0" encoding="UTF-8"?>
			<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="' . $xsdNamespace . '"></xsd:schema>');

        foreach ($classNames as $className) {
            $this->generateXmlForClassName($className, $viewHelperNamespace, $xmlRootNode);
        }

        return $xmlRootNode->asXML();
    }