两个类的配置和“持久态的困惑1”是一样的。

Account类(属性)：                                            

public class Account {

            public String accountNum;//账号号码 ,主键

            public Set subAccountSet = new HashSet();//SubAccount的Set集合

            }

Account类的配置文件：

SubAccount类：

public class SubAccount {

            public int subAccountId;  

            public String subAccountNum;   

public Account account; //外键

}

SubAccount类的配置文件：

由以上配置文件：Account和SubAccount是双向一对多关联

一下是我的一些验证：

public class HibernateUtil {

            public static SessionFactory sessionFactory = buildSessionFactory();

            private static SessionFactory buildSessionFactory(){

                       。。。。通过配置文件创建并返回sessionFactory对象

            }

            public static SessionFactory getSessionFactory(){

                       return sessionFactory;

            }

            public static void main(String[] args) {

                       // TODO Auto-generated method stub

                       SessionFactory sessionFactory = HibernateUtil.getSessionFactory();

                       Session session = sessionFactory.openSession();

                       session.beginTransaction();

//创建一个Account对象account

                       Account account = new Account();

                       account.setAccountNum("141");

//将account转化为持久态

                       session.save(account);//注意A

                       session.getTransaction().commit();

                       System.out.println("啦啦啦啦啦。。。");//注意B

//问题1.运行后会发现sql语句是在“注意B”打印的后的！！

            不是说save了就会立马发送sql语句到DB中执行吗？

//创建一个SubAccount对象subAccount

                       SubAccount subAccount = new SubAccount();

                       subAccount.setSubAccountNum("0201");

//下面，将transcient态的subAccount对象给add进account的Set集合中

                       account.getSubAccountSet().add(subAccount);//注意C

//问题2.虽然account已经save,就是说已经是持久态了，可是，"注意C"的语句汇报：not-null property references a null or transient value : cmbc.emen.po.SubAccount.account

/**

                       为什么处于持久态的account对象中的Set集合add入transcient态的subAccount对象时不会insert subAccount进入DB中的呢？

*/

                       session.getTransaction().commit();       

}

}