hibernate 3.1的应用问题

public class XingfuDAO extends BaseHibernateDAO {
private static final Log log = LogFactory.getLog(XingfuDAO.class);
public List findByExample(Xingfu instance) {
log.debug("finding Xingfu instance by example");
try {
List results = getSession().createCriteria("com.Xingfu").add(
Example.create(instance)).list();
log.debug("find by example successful, result size: "
+ results.size());
return results;
} catch (RuntimeException re) {
log.error("find by example failed", re);
throw re;
}
}
public List findByProperty(String propertyName, Object value) {
log.debug("finding Xingfu instance with property: " + propertyName
+ ", value: " + value);
try {
String queryString = "from Xingfu as model where model."
+ propertyName + "= ?";
Query queryObject = getSession().createQuery(queryString);