hibernate的template子查询

public List findAll(String dwmc) {
  log.debug("finding all ZwJbb instances");
  try {
   String queryString = "from ZwJbb z where z.lxdm in (select bmdm from pub_dw  where dwmc=?)";
   return getHibernateTemplate().find(queryString,dwmc);
  } catch (RuntimeException re) {
   log.error("find all failed", re);
   throw re;
  }
 }

结果为空指针。 

from ZwJbb z where z.lxdm in (select bmdm from pub_dw  where dwmc=?)

是否正确。

转为sql语句能执行成功且不为空。