On Mon, 28 Mar 2005 14:24:24 -0500, Laran Evans <[EMAIL PROTECTED]> wrote: > Am I correct in my interpretation that: > > When A extends B then A holds a Reference to A. > When A implements B then A is an Extent of B. > > ??? > > I'm having a bear of a time getting my inheritance working properly, > especially when "class C extends B implements A". > > Any advice would be appreciated.
I'm not entirely sure that I understand what you're asking here. Both "extends" and "implements" are Java keywords used for the same thing: inheritance. They differ only in that extends can only be used with classes whereas implements can only be used with interfaces. E.g., when A extends B then B must be a class (though it might be abstract) and when A implements C then C must be an interface. OJB does not care either way, for both you would use "extents" (note the difference to extends) which is the inverse, i.e. you would say that A has an extent B if B extends A (when A is a class) or B implements A (when A is an interface). You can have class-descriptors for both interfaces and classes, you only have to be careful when OJB tries to instantiate interfaces/abstract classes in which case you have to use factory-class+factory-method to define the factory method that creates the concrete instance. Tom --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
