Re: Change subclass at runtime ?

You can call forgetObject() after doing this and then refetch it (not 
fire a fault!).  I've done this is desperation a few times but it is 
NOT something that I'd want to reccomend for production code.  What you 
need to do is to change your design so that the different data / 
behaviour is in other objects.  Then, rather than change the class, you 
just change which object a relationship points to.  There is a name for 
this pattern, but I forget which now.  Delegate perhaps?  Or State?


Chuck


On Jun 20, 2004, at 9:42 AM, Dominique Schoenenberger wrote:

> I have inheritance in my application and sometimes I have to change 
> the subclass of a record. How to do that ?
>
> It is vertical inheritance so in theory, you have to change the class 
> discriminating attribute in the database but if you do this at run 
> time, the class may be already instanciated... do I have to refault 
> the object ? and what about relationship ?
>
> One of my solution to this problem is to create a new object of the 
> class we want to change to, copy all values of the properties of the 
> old object to the new one and then delete the old object. This is a 
> solution but it is much more complicated than changing the 
> discriminating attribute...
>
> Anybody having already found something for this ?
>
> Dominique
>
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