* @param request http request containing the query parameters.
* @param response http response to be sent.
* @throws Exception (for a variety of reasons detected while parsing and validating the http parms).
*/
private void performMultiQuery(HttpServletRequest request, HttpServletResponse response) throws Exception {
User user = AuthenticationUtils.getUserFromRequest(request);
String[] queriesStrings = request.getParameterValues("queries");
if( 1 != queriesStrings.length ) {
throw new Exception("Parameter 'queries' must be specified exactly oncce");
}