Using transient storage

[Frank Finger]

I'm using Netbeans MDR to transform a proprietary model format to UML
XMI (standalone). In every run of the transformation, I want to build
the model from scratch, export it, and throw the repository away
afterwards. That's why I thought that ...memoryimpl.StorageFactoryImpl
would be the storage implementation to use.
A single export works fine, but when exporting twice I run into
exceptions. The same exceptions can be produced by the piece of source
code below.
 From a quick look at ...mdr.persistence.memoryimpl.StorageImpl, I
thought that not assigning STORAGE_ID values would lead to independent
repositories.


public static void main( String[] args ) throws Exception
{
   Map properties = new HashMap();
   properties.put(
     "storage",
     "org.netbeans.mdr.persistence.memoryimpl.StorageFactoryImpl"
   );
   // I'm not setting the STORAGE_ID.
   // properties.put( StorageFactoryImpl.STORAGE_ID, ... );

   MDRepository firstRepository = new NBMDRepositoryImpl( properties );
   System.out.println(
     "firstRepository extents: "+
     Arrays.asList( firstRepository.getExtentNames() )
   );
   MDRepository secondRepository = new NBMDRepositoryImpl( properties );
   // following line throws exception:
   System.out.println(
     "secondRepository extents: "+
     Arrays.asList( secondRepository.getExtentNames() )
   );
}

The stack trace of the exception is:
org.netbeans.mdr.util.DebugException: Missing storage files or different
storage version.
   at ...storagemodel.MdrStorage.initializeIndexes(MdrStorage.java:507)
   at ...storagemodel.MdrStorage.rollback(MdrStorage.java:554)
   at ...util.TransactionMutex.end(TransactionMutex.java:73)
   at ...util.MultipleReadersMutex.leave(MultipleReadersMutex.java:173)
   at ...NBMDRepositoryImpl.endTrans(NBMDRepositoryImpl.java:249)
   at ...NBMDRepositoryImpl.boot(NBMDRepositoryImpl.java:1331)
   at ...NBMDRepositoryImpl.initCheck(NBMDRepositoryImpl.java:758)
   at ...NBMDRepositoryImpl.getExtentNames(NBMDRepositoryImpl.java:347)
   at Main.main(Main.java:58) /* ="secondRepository.getExtentNames()" */


Can anybody tell me what I'm doing wrong?

Thanks in advance,
Frank

[Steffen Zschaler]

Hi,

Why do you need to throw away the complete repository? Shouldn't it be
enough to delete the extents? This way you could reuse any generated JMI
stuff etc.

Ciao,

Steffen

Frank Finger wrote:

> I'm using Netbeans MDR to transform a proprietary model format to UML
> XMI (standalone). In every run of the transformation, I want to build
> the model from scratch, export it, and throw the repository away
> afterwards. That's why I thought that ...memoryimpl.StorageFactoryImpl
> would be the storage implementation to use.
> A single export works fine, but when exporting twice I run into
> exceptions. The same exceptions can be produced by the piece of source
> code below.
> From a quick look at ...mdr.persistence.memoryimpl.StorageImpl, I
> thought that not assigning STORAGE_ID values would lead to independent
> repositories.
>
>
> public static void main( String[] args ) throws Exception
> {
>   Map properties = new HashMap();
>   properties.put(
>     "storage",
>     "org.netbeans.mdr.persistence.memoryimpl.StorageFactoryImpl"
>   );
>   // I'm not setting the STORAGE_ID.
>   // properties.put( StorageFactoryImpl.STORAGE_ID, ... );
>
>   MDRepository firstRepository = new NBMDRepositoryImpl( properties );
>   System.out.println(
>     "firstRepository extents: "+
>     Arrays.asList( firstRepository.getExtentNames() )
>   );
>   MDRepository secondRepository = new NBMDRepositoryImpl( properties );
>   // following line throws exception:
>   System.out.println(
>     "secondRepository extents: "+
>     Arrays.asList( secondRepository.getExtentNames() )
>   );
> }
>
> The stack trace of the exception is:
> org.netbeans.mdr.util.DebugException: Missing storage files or
> different storage version.
>   at ...storagemodel.MdrStorage.initializeIndexes(MdrStorage.java:507)
>   at ...storagemodel.MdrStorage.rollback(MdrStorage.java:554)
>   at ...util.TransactionMutex.end(TransactionMutex.java:73)
>   at ...util.MultipleReadersMutex.leave(MultipleReadersMutex.java:173)
>   at ...NBMDRepositoryImpl.endTrans(NBMDRepositoryImpl.java:249)
>   at ...NBMDRepositoryImpl.boot(NBMDRepositoryImpl.java:1331)
>   at ...NBMDRepositoryImpl.initCheck(NBMDRepositoryImpl.java:758)
>   at ...NBMDRepositoryImpl.getExtentNames(NBMDRepositoryImpl.java:347)
>   at Main.main(Main.java:58) /* ="secondRepository.getExtentNames()" */
>
>
> Can anybody tell me what I'm doing wrong?
>
> Thanks in advance,
> Frank

--
Dipl.-Inf. Steffen Zschaler
Research Assistant

Technische Universität Dresden
Department of Computer Science

Phone [phone]
Fax   [phone]
Email Steffen.Zschaler@...
WWW   http://www.steffen-zschaler.de.vu/

[Martin Matula]

Try using different storage ids. Anyway, deleting the extents would save
more memory, since otherwise the repository is not garbage collected
unless the application ends.
Martin

Frank Finger wrote:

> I'm using Netbeans MDR to transform a proprietary model format to UML
> XMI (standalone). In every run of the transformation, I want to build
> the model from scratch, export it, and throw the repository away
> afterwards. That's why I thought that ...memoryimpl.StorageFactoryImpl
> would be the storage implementation to use.
> A single export works fine, but when exporting twice I run into
> exceptions. The same exceptions can be produced by the piece of source
> code below.
>  From a quick look at ...mdr.persistence.memoryimpl.StorageImpl, I
> thought that not assigning STORAGE_ID values would lead to independent
> repositories.
>
>
> public static void main( String[] args ) throws Exception
> {
>   Map properties = new HashMap();
>   properties.put(
>     "storage",
>     "org.netbeans.mdr.persistence.memoryimpl.StorageFactoryImpl"
>   );
>   // I'm not setting the STORAGE_ID.
>   // properties.put( StorageFactoryImpl.STORAGE_ID, ... );
>
>   MDRepository firstRepository = new NBMDRepositoryImpl( properties );
>   System.out.println(
>     "firstRepository extents: "+
>     Arrays.asList( firstRepository.getExtentNames() )
>   );
>   MDRepository secondRepository = new NBMDRepositoryImpl( properties );
>   // following line throws exception:
>   System.out.println(
>     "secondRepository extents: "+
>     Arrays.asList( secondRepository.getExtentNames() )
>   );
> }
>
> The stack trace of the exception is:
> org.netbeans.mdr.util.DebugException: Missing storage files or different
> storage version.
>   at ...storagemodel.MdrStorage.initializeIndexes(MdrStorage.java:507)
>   at ...storagemodel.MdrStorage.rollback(MdrStorage.java:554)
>   at ...util.TransactionMutex.end(TransactionMutex.java:73)
>   at ...util.MultipleReadersMutex.leave(MultipleReadersMutex.java:173)
>   at ...NBMDRepositoryImpl.endTrans(NBMDRepositoryImpl.java:249)
>   at ...NBMDRepositoryImpl.boot(NBMDRepositoryImpl.java:1331)
>   at ...NBMDRepositoryImpl.initCheck(NBMDRepositoryImpl.java:758)
>   at ...NBMDRepositoryImpl.getExtentNames(NBMDRepositoryImpl.java:347)
>   at Main.main(Main.java:58) /* ="secondRepository.getExtentNames()" */
>
>
> Can anybody tell me what I'm doing wrong?
>
> Thanks in advance,
> Frank

[Leonardo Gresta Paulino Murta]

Hi Frank,

    We have exactly the same scenario. What we do in each iteration is
to create a RefPackage, perform the translation, and then delete the
RefPackage. In this way we do not need to (re)initialize the whole
repository (load metamodel, etc.) time and again.

     Leo

PS.: Our repository is an in memory repository. We start it using the
following code:

Map<String,String> properties = new HashMap<String,String>();
properties.put("storage",
"org.netbeans.mdr.persistence.memoryimpl.StorageFactoryImpl");
properties.put(StorageFactoryImpl.STORAGE_ID,
String.valueOf(System.currentTimeMillis()));
repository = new NBMDRepositoryImpl(properties);  

Frank Finger escreveu:

> I'm using Netbeans MDR to transform a proprietary model format to UML
> XMI (standalone). In every run of the transformation, I want to build
> the model from scratch, export it, and throw the repository away
> afterwards. That's why I thought that ...memoryimpl.StorageFactoryImpl
> would be the storage implementation to use.
> A single export works fine, but when exporting twice I run into
> exceptions. The same exceptions can be produced by the piece of source
> code below.
> From a quick look at ...mdr.persistence.memoryimpl.StorageImpl, I
> thought that not assigning STORAGE_ID values would lead to independent
> repositories.
>
>
> public static void main( String[] args ) throws Exception
> {
>   Map properties = new HashMap();
>   properties.put(
>     "storage",
>     "org.netbeans.mdr.persistence.memoryimpl.StorageFactoryImpl"
>   );
>   // I'm not setting the STORAGE_ID.
>   // properties.put( StorageFactoryImpl.STORAGE_ID, ... );
>
>   MDRepository firstRepository = new NBMDRepositoryImpl( properties );
>   System.out.println(
>     "firstRepository extents: "+
>     Arrays.asList( firstRepository.getExtentNames() )
>   );
>   MDRepository secondRepository = new NBMDRepositoryImpl( properties );
>   // following line throws exception:
>   System.out.println(
>     "secondRepository extents: "+
>     Arrays.asList( secondRepository.getExtentNames() )
>   );
> }
>
> The stack trace of the exception is:
> org.netbeans.mdr.util.DebugException: Missing storage files or
> different storage version.
>   at ...storagemodel.MdrStorage.initializeIndexes(MdrStorage.java:507)
>   at ...storagemodel.MdrStorage.rollback(MdrStorage.java:554)
>   at ...util.TransactionMutex.end(TransactionMutex.java:73)
>   at ...util.MultipleReadersMutex.leave(MultipleReadersMutex.java:173)
>   at ...NBMDRepositoryImpl.endTrans(NBMDRepositoryImpl.java:249)
>   at ...NBMDRepositoryImpl.boot(NBMDRepositoryImpl.java:1331)
>   at ...NBMDRepositoryImpl.initCheck(NBMDRepositoryImpl.java:758)
>   at ...NBMDRepositoryImpl.getExtentNames(NBMDRepositoryImpl.java:347)
>   at Main.main(Main.java:58) /* ="secondRepository.getExtentNames()" */
>
>
> Can anybody tell me what I'm doing wrong?
>
> Thanks in advance,
> Frank
>