code: public String getNameId() throws Exception {
  		NodeList nodes = xmlDoc.getElementsByTagNameNS("urn:oasis:names:tc:SAML:2.0:assertion", "NameID");
  
  		if (nodes.getLength() == 0) {
  			throw new Exception("No name id found in document");
  		}
  
  		return nodes.item(0).getTextContent();
  	}
docs: Return the Response nameID (user identifier)
  
  @return String user nameID
  @throws Exception