//prepare parser
final Parser parser;
String clsnm = config.getInitParameter("parser-class");
parser = clsnm != null ?
(Parser)newInstance(clsnm, Parser.class): new ParserImpl();
//prepare manager
clsnm = config.getInitParameter("manager-class");
_manager = clsnm != null ?
(ZestManager)newInstance(clsnm, ZestManager.class): new ZestManager();