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Re: beginner question: Ozone & java.util collections



Thank you for your reply, I apologize for not formulating my question more 
clearly.

I was thinking of the case where the collection would be a database class. 
Our application has an entry point to the database which is a Repository 
class that returns Maps of business objects (e.g. Customers, Products) with 
keys of name or id. If my understanding is correct a similar implementation 
would require that the Maps be database classes since the Maps are 
manipulated directly. Otherwise Ozone would return a serialized version of 
the Map object to the client rather than a proxy and therefore adds & 
deletes to the Map on the client wouldn't be reflected in the Map object in 
the Ozone database.

One option would be to have a wrapper database class that passed the method 
calls through to the Map in an instance variable. Perhaps that is the best 
implementation.

Are there other options?

Such as making a java.util.TreeMap a database class so one could have:

Map customers = (Map)db.objectForName ("customers");

and do read, adds & deletes.

thanks again,

don



>
>On Wed, 14 Jun 2000, Don Berendsen wrote:
> > Is there an Ozone example available that uses java collections (e.g.
> > java.util.TreeSet) rather than the DXLib collections?
>You may use Java2 collections exactly as the Dx collections. I think no 
>sample
>is needed. Just type HashSet instead of DxHashSet for example (and change
>the enumerate/iterate code ;)
>
> >
> > As I understand the documentation all database classes in Ozone must
> > implement OzoneCompatible and the remote interface and be postprocessed. 
>I
> > understand how to write the remote interface but not how to do the
> > collection implementation.
>Yes, all *database* classes has to postprocessed. But usually collections 
>are
>not direct database classes. But they are members of database classes. In 
>this
>case nothing special has to be done with them.
>
> >
> > Any guidance would be greatly appreciated.
> >
> > cheers,
> >
> > donb
> >
> > BTW, I'm curious why the DXLib classes were used for Ozone instead of 
>the
> > standard Java collections. What's 'nifty' about them that isn't 'nifty'
> > about the Java collections?
>We started ozone with JDK1.0!
>
>On the other hand we can change the implementation if needed. For example 
>remove
>all array index checks for performance reasons.
>
>
>Falko
>--
>______________________________________________________________________
>Falko Braeutigam                         mailto:falko@softwarebuero.de
>softwarebuero m&b (SMB)                    http://www.softwarebuero.de
>

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