Why TransientObjectException?

duffymo · **Joined:** Wed Dec 17, 2003 10:13 am **Posts:** 33

Still struggling with Nick Heudecker's "Player/Team" example.

I've got a main that tries to instantiate instances of Player and Team and then persist them to an Oracle 9i database. I can see all positive messages flying by in my console window until I try to commit my transaction. Then I get this:

Code:

net.sf.hibernate.TransientObjectException: object references an unsaved transient instance - save the transient instance before flushing: example.Team

When I log into Oracle and query those tables, there are no rows saved.

What am I missing?

Here's the main method that exercises Hibernate:

Code:

    public static void main(String [] args)
    {
        if (args.length > 0)
        {
            Session session         = null;
            Transaction tx          = null;
            SessionFactory factory  = null; 

            try
            {   
                // configure Hibernate session
                Configuration config = new Configuration();
                
                config.addClass(example.Player.class);              
                config.addClass(example.Team.class);
                
                factory = config.buildSessionFactory();                
                session = factory.openSession();

                tx = session.beginTransaction();

                // create a new player
                Player p = new Player();
                Team team = new Team();
                p.setFirstName((args.length > 0) ? args[0] : "");
                p.setLastName((args.length > 1) ? args[1] : "");
                p.setDraftDate((args.length > 2) ? dateFormatter.parse(args[2]) : new Date());
                p.setAnnualSalary((args.length > 3) ? Float.parseFloat(args[3]) : 0.0f);
                p.setJerseyNumber((args.length > 4) ? Integer.parseInt(args[4]) : 0);
                team.setCity((args.length > 5) ? args[5] : "Boston");
                team.setName((args.length > 6) ? args[6] : "Celtics");                
                p.setTeam(team);
                team.addPlayer(p);

                System.out.println("player: " + p);
                System.out.println("team: " + team);
                
                session.saveOrUpdate(team);                                             
                session.saveOrUpdate(p);

                tx.commit();
                                                            
            }
            catch (Exception e)
            {
                if (tx != null)
                {
                     try { tx.rollback(); } catch (Exception ignore) { ; } 
                }
                e.printStackTrace();
            }
            finally
            {
                try
                {
                    java.sql.Connection connection = session.close();
                
                    if (connection != null)
                        connection.close();
                
                    factory.close();
                }
                catch (Exception ignore)
                {
                    // do nothing, you've done your best
                }                
            }
        }
    }

I've posted on this topic in other threads:

http://forum.hibernate.org/viewtopic.ph ... highlight=
http://forum.hibernate.org/viewtopic.ph ... highlight=
http://forum.hibernate.org/viewtopic.ph ... highlight=

I'm making progress, thanks to the forum's help. Sorry that it's so slow. - MOD

emmanuel · **Posted:** Tue Dec 23, 2003 1:09 pm

Check your team mapping. Consider using cascade="save-update" on the one-to-many to player to allow hibernate to save players when saving team.

Also consider using inverse="true" since you have a many-to-one on the other side. Have a look at http://www.hibernate.org/Documentation/InsideExplanationOfInverseTrue

PS: this is far easier with the mapping.

duffymo · **Joined:** Wed Dec 17, 2003 10:13 am **Posts:** 33

Thank you, Emmanuel, both for watching and for your help.

Still failed. I've got to be missing something else in my mapping.

I'm not sure I understand your PS. I'm following your advice from a previous thread and using XDoclet and Ant to regenerate my hbm.xml every time. What do you mean by "easier with the mapping"? Should I abandon XDoclet until this works? Are you suggesting that I modify the hbm.xml mappings directly? - MOD

emmanuel · **Posted:** Tue Dec 23, 2003 2:35 pm

No, it's easier for me to help with the mapping in the post. I have a mapping to issue translator in brain ;-)

duffymo · **Joined:** Wed Dec 17, 2003 10:13 am **Posts:** 33

I'm sorry - I'm not thinking clearly.

I did one experiment that makes me feel better. I removed the one-to-many and inverse relationships from both classes, altered the tables to eliminate the foreign key constraints, and re-ran the code to see if I could persist Player and Team objects. Both were successful (thank God).

As you're suggesting, it's my mistake with the one-to-many and inverse relationships that's causing the problem.

I've put back those XDoclet tags and regenerated the hbm.xml mappings:

example.Players.hbm.xml:

Code:

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 2.0//EN" 
    "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping>
    <class
        name="example.Player"
        table="players"
        dynamic-update="false"
        dynamic-insert="false"
    >

        <id
            name="id"
            column="player_id"
            type="long"
            unsaved-value="null"
        >
            <generator class="sequence">
            </generator>
        </id>

        <property
            name="annualSalary"
            type="float"
            update="true"
            insert="true"
            column="annual_salary"
        />

        <property
            name="draftDate"
            type="date"
            update="true"
            insert="true"
            column="draft_date"
        />

        <property
            name="firstName"
            type="string"
            update="true"
            insert="true"
            column="first_name"
            length="15"
        />

        <property
            name="jerseyNumber"
            type="integer"
            update="true"
            insert="true"
            column="jersey_number"
            length="1"
        />

        <property
            name="lastName"
            type="string"
            update="true"
            insert="true"
            column="last_name"
            length="15"
            not-null="true"
        />

        <many-to-one
            name="team"
            class="example.Team"
            cascade="save-update"
            outer-join="auto"
            update="true"
            insert="true"
            column="team_id"
        />

        <!--
            To add non XDoclet property mappings, create a file named
                hibernate-properties-Player.xml
            containing the additional properties and place it in your merge dir.
        -->

    </class>

</hibernate-mapping>

example.Teams.hbm.xml:

Code:

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 2.0//EN" 
    "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping>
    <class
        name="example.Team"
        table="teams"
        dynamic-update="false"
        dynamic-insert="false"
    >

        <id
            name="id"
            column="team_id"
            type="long"
            unsaved-value="null"
        >
            <generator class="sequence">
            </generator>
        </id>

        <property
            name="city"
            type="string"
            update="true"
            insert="true"
            column="city"
            length="15"
            not-null="true"
        />

        <property
            name="name"
            type="java.lang.String"
            update="true"
            insert="true"
            column="name"
            length="20"
            not-null="true"
        />

        <set
            name="players"
            table="players"
            lazy="true"
            inverse="true"
            cascade="all"
            sort="unsorted"
        >

              <key
                  column="player_id"
              />

              <one-to-many
                  class="example.Player"
              />
        </set>

        <!--
            To add non XDoclet property mappings, create a file named
                hibernate-properties-Team.xml
            containing the additional properties and place it in your merge dir.
        -->

    </class>

</hibernate-mapping>

I reviewed the documentation more carefully this time, because I believe it worked. If you spot anything else that I ought to correct, I'd appreciate hearing about it.

One question: the players table has a foreign key to the teams table, but the inverse is NOT true. Correct? (Makes sense for one-to-many, I guess.)

But thanks again for your help and patience. Sincerely, MOD

emmanuel · **Posted:** Wed Dec 24, 2003 4:29 am

You screwed the set key. It must refer the "parent" object id

Code:

<set
            name="players"
            table="players"
            lazy="true"
            inverse="true"
            cascade="all"
            sort="unsorted"
        >

              <key
                  column="player_id"
              />

must be replaced by

Code:

<set
            name="players"
            table="players"
            lazy="true"
            inverse="true"
            cascade="all"
            sort="unsorted"
        >

              <key
                  column="team_id"
              />

Quote:

One question: the players table has a foreign key to the teams table, but the inverse is NOT true. Correct? (Makes sense for one-to-many, I guess.)

Correct

duffymo · **Joined:** Wed Dec 17, 2003 10:13 am **Posts:** 33

Ack! Thank you again, Emmanuel. My best to you for the holidays. Sincerely, MOD