NamespaceHelper namespaceHelper = new NamespaceHelper(PageEnvelope.NAMESPACE,
PageEnvelope.DEFAULT_PREFIX, document);
metaElement = namespaceHelper.getFirstChild(topMetaElement, getLocalElementName());
if (metaElement == null) {
metaElement = namespaceHelper.createElement(getLocalElementName());
Element[] children = DocumentHelper.getChildren(topMetaElement);
if (children.length == 0) {
topMetaElement.appendChild(metaElement);
} else {
topMetaElement.insertBefore(metaElement, children[0]);