dom w3c dom DOMException w3c dom DOMImplementation w3c dom w3c dom DocumentType w3c dom psvidomimplementationimpl coredomimplementationimpl psvidomimplementationimpl singleton psvidomimplementationimpl domimplementation getdomimplementation singleton hasfeature feature version super.hasfeature feature version feature.equalsignorecase createdocument namespaceuri qualifiedname documenttype doctype domexception doctype doctype.getownerdocument domexception domexception.wrong_document_err dommessageformatter.formatmessage dommessageformatter.xml_domain documentimpl doc psvidocumentimpl doctype qualifiedname namespaceuri doc.createelementns namespaceuri qualifiedname doc.appendchild doc