stax events xml namespace QName xml stream Location xml stream events Namespace elementimpl xmleventimpl qname fnamespaces elementimpl qname name isstartelement namespaces location location isstartelement start_element end_element location name namespaces namespaces.hasnext fnamespaces namespace ns namespace namespaces.next fnamespaces.add ns namespaces.hasnext fnamespaces collections.empty_list qname getnamespaces createimmutableiterator fnamespaces.iterator createimmutableiterator iter noremoveiterator iter noremoveiterator fwrapped noremoveiterator wrapped fwrapped wrapped hasnext fwrapped.hasnext fwrapped.next remove unsupportedoperationexception