puzzle with session.saveOrUpdate

worldcreatxr · **Joined:** Sat Apr 10, 2004 8:39 pm **Posts:** 84

puzzle with session.saveOrUpdate

I have two DAO class , they implement a method named saveOrUpdate.
It's codes like:

Code:

   public Serializable saveOrUpdate(Object obj) throws DataAccessException {
      Session session = null;
      try {
         session = sessionFactory.openSession();
         session.saveOrUpdateCopy(obj);
         session.flush();
         return obj;
      } catch (HibernateException he) {
         throw SessionFactoryUtils.convertHibernateAccessException(he);
      } finally {
         SessionFactoryUtils
               .closeSessionIfNecessary(session, sessionFactory);
      }
   }

problem 1:

Code:

Folder folder = folderDao.loadByPrimaryKey(0);

for (int i=0; i<array.length; i++) {

      Topic topic = new Topic();
[color=red]      topic.setFolder(folder)[/color]
.....................

     if (topic.getCreateTime().before(folder.getMinTime()))  {
         folder.setMinTime(topic.getCreateTime);
    }

[color=red]    topicDao.saveOrUpdate(topic);
    folderDao.saveOrUpdate(folder);    [/color]
}

I found after folderDao.saveOrUpdate(folder) excuted ,
the saved topic objecs's field of folder be set to null.

what's the problem?

if I use this codes:

Code:

topicDao.(topic);
    folderDao.update(folder);    

It's OK. what's the problem?

=========================================

problem 2:

I 've two table it's sql is

Code:

create table xtype (
   symbol varchar(16) not null,
   title varchar(30) default 'no title' not null,
   note varchar(256),

   primary key(symbol)
);

create table pigeonhole_rule (
   xtype_symbol varchar(16) not null,
   pigeonhole_type_symbol varchar(16),

   primary key(xtype_symbol),
   foreign key(xtype_symbol) references xtype(symbol),
   foreign key(pigeonhole_type_symbol) references         pigeonhole_type(symbol)
);

when I save or update xtype object, it try to update pigeonhole_rule.
it try to set the foreigh key in pigeonhole_rule to null, but the foreign key is also primary key. so it's cast exception.

How to ?

I 've set cascade="none" in Xtype.hbm.xml

Code:

    <set name="setOfPigeonholeRule" cascade="none">
      <key>
        <column name="XTYPE_SYMBOL" length="16" not-null="false"
        unique="true"  />
      </key>

      <one-to-many
      class="demos.orm.PigeonholeRule" />
    </set>

    <one-to-one
        name="pigeonholeRule"
        class="demos.orm.PigeonholeRule"
        outer-join="auto"
        cascade="none"
    />

and set cascade="none" in PigeonholeRule.hbm.xml

Code:

    <!-- bi-directional one-to-one association to Xtype -->

    <one-to-one
        name="xtype"
        class="demos.orm.Xtype"
        outer-join="auto"
        constrained="true"
        cascade="none"
    />

  </class>

Hibernate: update XTYPE set TITLE=?, NOTE=? where SYMBOL=?
Hibernate: update PIGEONHOLE_RULE set XTYPE_SYMBOL=null where XTYPE_SYMBOL=?[WARN ] [2005-03-29 15:15:53,890] net.sf.hibernate.util.JDBCExceptionReporter - SQL Error: 0, SQLState: null
[ERROR] [2005-03-29 15:15:53,890] net.sf.hibernate.util.JDBCExceptionReporter - failed batch
[WARN ] [2005-03-29 15:15:53,890] net.sf.hibernate.util.JDBCExceptionReporter - SQL Error: 0, SQLState: null
[ERROR] [2005-03-29 15:15:53,890] net.sf.hibernate.util.JDBCExceptionReporter - failed batch
[ERROR] [2005-03-29 15:15:53,890] net.sf.hibernate.impl.SessionImpl - Could not synchronize database state with session