List<VariantSet> rsS = null;
        if (pk_user == null) {
            dao.setSql(getStuSql);
            Map<String, String> stuParam = new HashMap<String, String>();
            stuParam.put("pk_arrange", pk_arrange);
            rsS = dao.queryForList(stuParam);
        } else {
            List listStu = new ArrayList<VariantSet>();
            for (int i = 0; i < pk_user.length; i++) {
                //Log.error(pk_user[i]+"====================");
                listStu.add(pk_user[i]);
            }
            rsS = listStu;
        }
for (VariantSet vsS : rsS) {//此处报错。该如何修改求高手解答
}