net.sf.hibernate.NonUniqueObjectException!?

nerotnt · **Joined:** Wed Oct 08, 2003 10:31 am **Posts:** 247

I'm getting the following error:

net.sf.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: pt.comseal.arsol.vo.VersaoDocumentoPK@b113c7[id=1,documento=pt.comseal.arsol.vo.Documento@1cf662f[id=2]], of class: pt.comseal.arsol.vo.VersaoDocumento
at net.sf.hibernate.impl.SessionImpl.checkUniqueness(SessionImpl.java:1605)
( ... )

To try to solve this I did a "session.evict(doc_aux);" below in the "Method code" section but with no success.
I also tried to use a second Session and going a "get" on the Documento with that session instance and still with no success.
I first do a "get" on Documento to see if it exists and then I do a "get on VersaoDocumento to see if it exists also. The second "get" is the one that's throwing the exception because VersaoDocumento has a composite-id VersaoDocumentoPK which has a Documento as one of its components.

Please help. Don't understand the error.

------------------------------------------
Mapping files (generated with R3)
------------------------------------------
Documento

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>
<!-- 
    Created by Middlegen Hibernate plugin

    http://boss.bekk.no/boss/middlegen/
    http://hibernate.sourceforge.net/
-->

<class 
    name="vo.Documento" 
    table="documento"
>

    <id
        name="id"
        type="long"
        column="id"
    >
        <generator class="increment" />
    </id>

    <property
        name="nome"
        type="java.lang.String"
        column="nome"
        length="-1"
    />

    <!-- associations -->
    <!-- bi-directional one-to-many association to VersaoDocumento -->
    <set
        name="versaoDocumentos"
        lazy="true"
        inverse="true"
    >
        <key>
            <column name="documento_fk" />
        </key>
        <one-to-many 
            class="vo.VersaoDocumento"
        />
    </set>

</class>
</hibernate-mapping>

VersaoDocumento

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>
<!-- 
    Created by Middlegen Hibernate plugin

    http://boss.bekk.no/boss/middlegen/
    http://hibernate.sourceforge.net/
-->

<class 
    name="vo.VersaoDocumento" 
    table="versao_documento"
>

    <composite-id name="comp_id" class="vo.VersaoDocumentoPK">
        <key-property 
            name="id" 
            column="id" 
            type="long"
            length="8"
        />
        <!-- bi-directional many-to-one association to Documento -->
        <key-many-to-one
           name="documento"
           class="vo.Documento"
       >
           <column name="documento_fk" />
       </key-many-to-one>
    </composite-id>    

    <property
        name="descricao"
        type="java.lang.String"
        column="descricao"
        length="-1"
    />
 
    <!-- associations -->

</class>
</hibernate-mapping>

-------------------
Method code
-------------------

Code:

( ... )
SessionFactory sessionFactory = HibernateFactory.createFactory();   
session = sessionFactory.openSession();
transaction = session.beginTransaction();
         
Documento doc_aux = (Documento)session.get(Documento.class, documento.getId());
if(doc_aux == null) {
   throw new ObjectoNaoEncontradoException("Error.");
}

VersaoDocumento versao_doc = (VersaoDocumento)documento.getVersaoDocumentos().iterator().next();
session.evict(doc_aux);
         
if((VersaoDocumento)session.get(VersaoDocumento.class, versao_doc.getComp_id()) == null) {
   throw new ObjectoNaoEncontradoException("Error.");
}

session.saveOrUpdate(documento);
session.saveOrUpdate(versao_doc);

transaction.commit();
session.close();
( ... )

michael · **Posted:** Tue Dec 30, 2003 9:19 am

Thats pretty logical:

VersaoDocumento versao_doc = (VersaoDocumento)documento.getVersaoDocumentos().iterator().next();
session.evict(doc_aux); This

if((VersaoDocumento)session.get(VersaoDocumento.class, versao_doc.getComp_id()) == null) {
throw new ObjectoNaoEncontradoException("Error.");
} Is the same as loaded here

Why do you do the second load anyways? If you want to refresh the object from the db, use session.refresh()

The whole thing looks strange to me, first you get an object out of a collection loaded from the db, and then you want to check again if it exists in the db?

emmanuel · **Posted:** Tue Dec 30, 2003 9:29 am

Are equals and hashCode properly implemented for VersaoDocumento and it's PK.

Wht you're doing is :

the exception is expected

nerotnt · **Joined:** Wed Oct 08, 2003 10:31 am **Posts:** 247

gloeglm wrote:

Thats pretty logical:

VersaoDocumento versao_doc = (VersaoDocumento)documento.getVersaoDocumentos().iterator().next();
session.evict(doc_aux); This

if((VersaoDocumento)session.get(VersaoDocumento.class, versao_doc.getComp_id()) == null) {
throw new ObjectoNaoEncontradoException("Error.");
} Is the same as loaded here

...

I do the second test because I can have the following test code:

Code:

Documento documento = new Documento();
documento.setId(new Long(2));
documento.setNome("xpto");
      
HashSet versao_docs = new HashSet();
VersaoDocumento versao_doc = new VersaoDocumento();
VersaoDocumentoPK versao_doc_pk = new VersaoDocumentoPK();
versao_doc_pk.setId(1); // <-------- (1)
versao_doc_pk.setDocumento(documento);
versao_doc.setComp_id(versao_doc_pk);
      
versao_doc.setDescricao("smith");
      
versao_docs.add(versao_doc);
documento.setVersaoDocumentos(versao_docs);

// execute method for to update "documento"

And the client side can in fact, in (1) can do a "versao_doc_pk.setId();" to a value that could not exist. That's why I'm doing the second "get". And the first "get" doesn't tell me if the associated VersaoDocumento exists.
Another thing: I don't want to refresh the object from the DB. Just want to see if it exists. I may be misunderstanding something...