Hi Ken, Sorry, I wasn't very specific. You are correct in that the implementation class-descriptor should be declared as an extent of the interface class-descriptor. The interface class-descriptor does not require any field attributes to be declared for it.
Wally -----Original Message----- From: Ken Brewer [mailto:[EMAIL PROTECTED] Sent: Monday, November 17, 2003 8:29 AM To: OJB Users List; [EMAIL PROTECTED] Subject: RE: dynamic proxy HOWTO+ Thanks. Do you mean that the interface should be an extent-class inside the implementation class-descriptor? It seems that it should be the other way around e.g. the implementation class would be an extent-class inside the interface class-descriptor? > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Sent: Monday, November 17, 2003 2:22 AM > To: OJB Users List > Subject: Re: dynamic proxy HOWTO+ > > > Hi Ken, > > Ken Brewer wrote: > > I just started using OJB and so far so good. I'm confused about > the dynamic > > proxies. Previous to OJB, my object model used inheritance but no > > interfaces. Because I want lazy loading, I created an interface > for nearly > > every class. I simply named these interfaces 'I + classname' > e.g. Account > > now has an interface IAccount. I noticed that I had to change > my cast from > > the class to the interface when retrieving collection elements. > > > > 1. My application is substantially complete and has many > references to the > > class names e.g. Account. it seems I should have used the scheme > > Account(interface) & AccountImpl(class) in order to avoid breaking > > my application code references to Account, RIGHT? > > The OJB proxy mechanism provides a wrapper implementation for the > concrete AccountImpl. This wrapper implementation (which does the lazy > load) implements the interface Account. > So in you business object you always have to use the interface Account > to work safely with proxies. Of course it makes sense to have > convenient naming convention to differentiate between interfaces and > proxies. But OJB does not force you to any special names. > > > 2. When casting objects from a collection, should I cast to the > class name > > or proxy interface name? > > When using proxies always use the interface name. see explanation > above. > > > 3. Must I include the full hierarchy, including interfaces, in my > > repository.xml even though the interfaces are for dynamic proxies > > only? > > You must include at least one extent definition for the interface to > allow OJB to perform queries against that interface type. But you do > not have to declare the complete hierarchy. > > > 4. In the repository.xml, it seems that all superclass elements must > > be duplicated in each subclass? Is that correct? > > That depends on the mapping strategy. See > http://db.apache.org/ojb/tutorial3.html#mapping%20inheritance%20hi erarchies for details. cu, Thomas > > Thanks, > > -ken > > > > --------------------------------------------------------------------- > 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] --------------------------------------------------------------------- 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]
