request里获取参数.
用org.apache.velocity.tools.view.tools.ParameterParser类
example
public void setup(HttpServletRequest req)
{
ParameterParser pp = new ParameterParser(req);
setCriteria(pp.getString("find"));
setIndex(pp.getInt("index", 0));
setItemsPerPage(pp.getInt("show", DEFAULT_ITEMS_PER_PAGE));
}