Hi Archie, > > Hi, > Yes, I agree your statement. I like OJB, but > sometimes I feel OJB does not continue enhanceing its > mapping capability.
Just after the anonymous field feature we introduced a feature for mapping inheritance hierarchies on multiple joined tables: http://db.apache.org/ojb/tutorial3.html#mapping%20classes%20on%20multiple%20 joined%20tables > Hibernate does have better mapping > capability. Mhh. I've checked the Hibernate Mapping documentation and did not see anything that is not possible with OJB. What exactly is missing? We are happy to implement new features if users are requesting them. I think that Hibernate is very good at providing a feature set that covers many real world problems out of the box. The OJB mindset is a bit different. It goes like "We provide you with a flexible infrastructure that will allow you to build you persistence layer of choice". Maybe OJB should provide more out of the box solutions for typical mapping problems? Please let us know what exactly you would like to see! thanks for your input, thomas > Since the introduction of "anonymous > field" into OJB which I quite like it, OJB does not > improve mapping capability much. Maybe too much effort > is taken on JDO implementation. But since JDO 1.0 > itself does not regulate much about OR mapping (it is > heard that in 2.0, much regulatin will be made), good > OR mapping mechanism should be borrowed from some > other good ideas like Hibernate. > > By the way, I like the embedded (nested) field > function in OJB. Hibernate has similar function called > component, but for deeper nesting its configuration is > not that easy. > > Archie > > --- Rice Yeh <[EMAIL PROTECTED]> wrote: > > > > > > Hi, > > > I have been using OJB for some period. I am > > taking > > > a > > > project left by a partner that uses Hinbernate for > > > persistence. So I start studying Hibernate. > > > Hibernate > > > has a mapping function called "any type mapping" > > > that > > > is defined as the follows: > > > > > > "The <any> mapping element defines a polymorphic > > > association to classes from multiple tables. This > > > type > > > of mapping always requires more than one column. > > The > > > first column holds the type of the associated > > > entity. > > > The remaining columns hold the identifier. It is > > > impossible to specify a foreign key constraint for > > > this kind of association, so this is most > > certainly > > > not meant as the usual way of mapping > > (polymorphic) > > > associations." > > > > > > This kind of mapping is quite useful when dealing > > > with > > > fields of java.lang.Object or interface. However, > > as > > > I > > > know, there is no such support in OJB. I try to > > > study > > > the source code of OJB, but am still not able to > > > figure out the way to modify it (The xml mapping > > > handling code is a little hard to understand, just > > > wonder if it is possible to re-write it with Jibx > > to > > > make it more concise). > > > > > > Regards, > > > Rice > > > > > > > > > __________________________________ > > > Do you Yahoo!? > > > Exclusive Video Premiere - Britney Spears > > > http://launch.yahoo.com/promos/britneyspears/ > > > > > > > > > --------------------------------------------------------------------- > > > To unsubscribe, e-mail: > > > [EMAIL PROTECTED] > > > For additional commands, e-mail: > > > [EMAIL PROTECTED] > > > > > > > > > __________________________________ > > Do you Yahoo!? > > Exclusive Video Premiere - Britney Spears > > http://launch.yahoo.com/promos/britneyspears/ > > > __________________________________ > Do you Yahoo!? > Exclusive Video Premiere - Britney Spears > http://launch.yahoo.com/promos/britneyspears/ > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
