java - 无法从数据库 hql 检索项目

Question

有这个代码:

Session session = HibernateUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();
Query query = session.createQuery("from DBUser where id=1");
    for(Iterator it=query.iterate();it.hasNext();){
    Object[] row = (Object[]) it.next();
    System.out.println("ID: " + row[0]);
    System.out.println("Name: " + row[1]);
    System.out.println("Amount: " + row[2]);
}

发生错误:java.lang.ClassCastException:com.mycompany.app.DBUser 无法转换为 [Ljava.lang.Object;

可能有更简单的方法来从表中检索单个元素？

Answer 1

hql 在这种情况下返回映射类型。您的代码应如下所示:

Session session = HibernateUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();
Query query = session.createQuery("from DBUser where id=1");
    for(Iterator it=query.iterate();it.hasNext();){
    DBUser row = (DBUser) it.next();
    System.out.println("ID: " + row.getId());
    System.out.println("Name: " + row.getName());
    System.out.println("Amount: " + row.getAmount());
}