RE : [mdr-dev] Getting a null pointer exception while commiting

Hi Martin,

In fact, the model is converted from a XMI/UML model to XMI/MOF using
and imported into MDR. I have importing the problem, and in fact you are
pointing a bug in the XML database I'm using to store XMI files.

Even stranger, some XMI.field contain a boolean value (true or false).
One of them is corrupted.

I have attached a ZIP archive which contain two XML files:
	- Model_RTM.xml, the original file
	- Stored_RTM.xml, the content returned by eXist 0.9.2

Regards.

Olivier.

-----Message d'origine-----
De : Martin Matula [mailto:[email protected]] 
Envoyé : mercredi 3 septembre 2003 23:52
À : [email protected]
Objet : Re: [mdr-dev] Getting a null pointer exception while commiting


Hi Olivier,
it is strange that you are able to read the attached model. When I tried

to import it, XMI reader complained about the format of the XMI file 
(empty <XMI.field> tags are not supported - you have them in the 
multiplicity). After I replaced all <XMI.field/> by 
<XMI.field>1</XMI.field>, I successfully imported the metamodel and 
instantiated it without any exception.
Regards,
Martin

Olivier RICHAUD wrote:
> I'm trying to instanciate the model (see attachment) and when I commit

> the surrounding Read/Write transaction, I get the following exception:
> 
> org.netbeans.mdr.persistence.StorageTransientDataException:
> java.lang.NullPointerException: null
>         at 
> org.netbeans.mdr.persistence.btreeimpl.btreestorage.BtreeDatabase.writ
> eS
> treamable(BtreeDatabase.java:877)
>         at
>
org.netbeans.mdr.persistence.btreeimpl.btreestorage.BtreeDatabase.addRec
> ord(BtreeDatabase.java:916)
>         at
>
org.netbeans.mdr.persistence.btreeimpl.btreestorage.BtreeDatabase.save(B
> treeDatabase.java:502)
>         at
>
org.netbeans.mdr.persistence.btreeimpl.btreestorage.BtreeDatabase.commit
> Changes(BtreeDatabase.java:418)
>         at
>
org.netbeans.mdr.persistence.btreeimpl.btreestorage.BtreeStorage.commitC
> hanges(BtreeStorage.java:313)
>         at
> org.netbeans.mdr.storagemodel.MdrStorage.save(MdrStorage.java:532)
>         at
> org.netbeans.mdr.storagemodel.MdrStorage.commit(MdrStorage.java:503)
>         at
>
org.netbeans.mdr.util.TransactionMutex.leave(TransactionMutex.java:183)
>         at
>
org.netbeans.mdr.NBMDRepositoryImpl.endTrans(NBMDRepositoryImpl.java:202
> )
>         ...
> 
> 
> 
> When importing my model, I perform some checks to ensure the model can

> be correctly instantiated.
> 
> Before committing, I dont't have any problem creating  a new extent. I

> can see a valid MOF ID for my nex extent. But as soon as I commit, 
> this exception is raised and, of course, when I try to find the 
> extent, a null reference is returned, indicating no such extent exist.
> 
> Nevertheless, this may be linked to my model because I can correctly 
> instanciate another model. But I don't understand.
> 
> The MDR build number is : 200307311024 (MDR Standalone).
>  
> Thanks for your help.
> 
> Regards.
> 
> Olivier.