one-to-one and <generator class="foreign"

gbonnard · **Posted:** Thu Nov 20, 2003 10:54 am

Dear all,
I've got the following situtation between 2 tables Edition and Index Edition with a one-to-one relation i.e the PK of Edition is also the PK of IndexEdition. The pb is that the PK of Index Edition is a sequence, therefore the data are inserted in IndexEdition but not in Edition.

Please HELP I become crazy !

The mapping is as follows :

<hibernate-mapping>
<class name="EditionPersistent" table="EDITION">
<id name="numEdition" column="PK_EDITION" unsaved-value="any">
<generator class="foreign"/>
</id>
......
</class>
</hibernate-mapping>

<hibernate-mapping>
<class name="IndexEditionPersistent" table="INDEX_EDITION">
<id name="numIndexEdition" column="PK_INDEX_EDITION">
<generator class="sequence">
<param name="sequence">S_INDEX_EDITION</param>
</generator>
....
<one-to-one name="edition" class="EditionPersistent" cascade="all" constrained="true"/>
</class>
</hibernate-mapping>

I've got the following message (error?) :
- reflection optimizer disabled for: EditionPersistent, NullPointerException: null

gavin · **Posted:** Thu Nov 20, 2003 10:59 am

Ah you actually need the class with the foreign generator to have an inverse <one-to-one> and mention that propety in a <param> tag. But actually, the side with the foreign generator needs to be the side with constrained="true" .... so I'm not so sure how well it works for you.

Check the Hibernate tests package for an example of correct usage.

gbonnard · **Posted:** Thu Nov 20, 2003 11:02 am

gavin wrote:

Ah you actually need the class with the foreign generator to have an inverse <one-to-one> and mention that propety in a <param> tag. But actually, the side with the foreign generator needs to be the side with constrained="true" .... so I'm not so sure how well it works for you.

Check the Hibernate tests package for an example of correct usage.

Actually it doesn't work at all !!!

gavin · **Posted:** Thu Nov 20, 2003 11:04 am

ummmm .... what do you mean?

yes, it works .... if you use it as intended....

gbonnard · **Posted:** Thu Nov 20, 2003 11:06 am

gavin wrote:

ummmm .... what do you mean?

yes, it works .... if you use it as intended....

There's definitively a pb with the class="foreign" for the id and i can't find what the f... it is !

gavin · **Posted:** Thu Nov 20, 2003 11:07 am

Look at the examples in the test package.

I'm repeating myself here I think.

gbonnard · **Posted:** Thu Nov 20, 2003 11:13 am

gavin wrote:

Look at the examples in the test package.

I'm repeating myself here I think.

You are speaking about the example of the cat ?
Actually I should use a 'meet in the middle' method so I can't change anything, neither DB model not OM.
Moreover it works without any sequence if I assign the key but as soon as I had a sequence it doesn't work

Brannor McThife · **Posted:** Thu Nov 20, 2003 11:18 am

To stop the to-and-fro...here's my example...and it works... :P

Code:

<class name="dse6.cdl.impl.XMLImpl" table="XML">
    <id name="XMLID" column="XMLID" type ="java.lang.Long" unsaved-value="null">
        <generator class="identity"/>
    </id>
...
    <one-to-one name="Matter" class="dse6.cdl.impl.MatterImpl" cascade="all"/>
</class>

and the other side:

Code:

<class name="dse6.cdl.impl.MatterImpl" table="Matter">
    <id name="XMLID" column="XMLID" type ="java.lang.Long" unsaved-value="null">
        <generator class="foreign">
            <param name="property">XML</param>
        </generator>
    </id>
...
    <one-to-one name="XML" class="dse6.cdl.impl.XMLImpl" constrained="true"/>
</class>

Modify yours to match that...and it should work. :)

-G

gbonnard · **Posted:** Thu Nov 20, 2003 11:39 am

No it doesn't work :( ... exception : unmapped property. So let's see the code :

Java class :

Code:

public class EditionPersistent
{
   private int numEdition ;
   private byte[] document ;
   
   // .....
   // + getter and setter
}

public class IndexEditionPersistent
{
   //key
   private int numIndexEdition ;
   private EditionPersistent edition;
  
  // .....
  // + getter and setter
}

Table script

Code:

CREATE TABLE INDEX_EDITION (
   PK_INDEX_EDITION NUMBER ( 10 ) NOT NULL,  <-- SEQUENCE
   TYPE NUMBER ( 1 ) NOT NULL,
   CLE NUMBER ( 10 ) NOT NULL,
   DATE_CREATION DATE NOT NULL,
   CONSTRAINT PK_INDEX_EDITION_1 PRIMARY KEY (PK_INDEX_EDITION)
   );

CREATE TABLE EDITION (
   PK_EDITION NUMBER ( 10 ) NOT NULL,
   DOCUMENT BLOB NOT NULL,
   CONSTRAINT PK_EDITION_1 PRIMARY KEY (PK_EDITION)
   );
ALTER TABLE EDITION ADD ( CONSTRAINT FK_EDITION_1 FOREIGN KEY (PK_EDITION) REFERENCES INDEX_EDITION (PK_INDEX_EDITION));

Brannor McThife · **Posted:** Thu Nov 20, 2003 12:02 pm

Did you do as Gavin said and add in the <one-to-one> in the foreign class? Along with the constrained option?

Do you actually "create sequence S_INDEX_EDITION" ?

-G

emmanuel · **Posted:** Thu Nov 20, 2003 12:05 pm

If you can't change the OM and don't have a reverse one-to-one, so replace foreign with assigned and set it manually

gbonnard · **Posted:** Thu Nov 20, 2003 12:18 pm

Brannor McThife wrote:

Did you do as Gavin said and add in the <one-to-one> in the foreign class? Along with the constrained option?

Do you actually "create sequence S_INDEX_EDITION" ?

-G

Yes I did

gbonnard · **Posted:** Thu Nov 20, 2003 12:29 pm

epbernard wrote:

If you can't change the OM and don't have a reverse one-to-one, so replace foreign with assigned and set it manually

But I can't it is a sequence !!!

emmanuel · **Posted:** Thu Nov 20, 2003 1:14 pm

Try

Code:

IndexEditionPersistent idx = new IndexEditionPersistent();
//fill in
session.save(idx);
EditionPersistent ed = new EditionPersistent();
ed.setNumEdition(idx.getNumIndexEdition());
session.save(ed);

session.flush();

I'm not sure of me, though

gavin · **Posted:** Thu Nov 20, 2003 1:19 pm

yes, that would work.