请问如何适用Hibernate API中public Query createSQLQuery(String sql, String[] returnAliases,Class[] returnClasses)

Question

可能是你sql错了, 修改一下catch部分:catch (Exception ex) {
      throw new DAOException("Query the FirstLevelProjectIte occur errors:", ex);
    }==>catch (Exception ex) {
      ex.printStackTrace();
    }

Answer 1

java.lang.UnsupportedOperationException: SQL queries do not currently support iteration
简单翻译一下：
‘java.lang.UnsupportedOperationException: Sql查询目前不支持iteration’

Answer 2

哦, 你用的是原生sql查询。 你还是用list吧。

Answer 3

試試下面是否可以？ 
public Iterator FirstLevelProjectIte() throws DAOException {
    Iterator firstLevelProjectIte = null;
    try {
      firstLevelProjectIte = session.createSQLQuery(
              " select {p.*},{t.*}" +
              " from project {p},task {t} " +
              " where {p}.id={t}.project_id ", new String[] {"p", "t"},
              new Class[] {Project.class, Task.class}).list().iterator();
      return firstLevelProjectIte;
    } catch (Exception ex) {
      throw new DAOException("Query the FirstLevelProjectIte occur errors:", ex);
    }
  }
 
public static void main(String[] args) throws DAOException,
          HibernateException {
    ProjectDAO dao = new HibernateProjectDAOImpl();
        Iterator ite = dao.FirstLevelProjectIte();     if (ite.hasNext()) {
          Object[] o = (Object[]) ite.next();
      for (int i = 0; i < o.length; i++) {
 
        Project project = null;
 
        try {
          project = dao.findByPK(2);
             if (o[i].equals(project)) {
               System.out.println("obj:" + project.getDescription());
             }
        } catch (DAOException ex) {
            ex.printStackTrace();
        } catch (DataNotFoundException ex) {
             ex.printStackTrace();
        }
      }
    }
  }