Re: custom xmlrpc marshallers

[Alexander Larsson <alexl redhat com>]

On Thu, 2005-03-17 at 18:24 -0500, Jonathan Blandford wrote:
> Alexander Larsson <alexl redhat com> writes:
> 
> > I added some highly magic code that lets you register marshallers and
> > demarshallers for custom type for the XmlRpcHandler.
> > 
> > Check out ActiveTopic for an example of how to use it. With that i can
> > just define xmlrpc handler methods like:
> > 
> >   public Vector getLiveComment(ActiveTopic topic, int commentId) {
> > 
> > The conversion from the topic long id (which is passed as a string due
> > to 64bit ints parameters not being in xmlrpc) to the looked up
> > ActiveTopic is magically handled in the lower layers.
> 
> This is really cool!!  We used it to add the chat feature today.
> 
> One issue we ran into was that it doesn't seem to recursively convert
> types.  For example, we returned a class (hashtable) with a Vector as an
> element.  That Vector contained classes, which were not auto marshalled.
> We had to call something like:
> 
>   Vector marshalledMessages = new Vector();
>   for (int i = 0; i < messages.size(); i++) {
>           Message msg = (Message) messages.get(i);
>           marshalledMessages.add(msg.marshalToHash());
>   }
> 
> by hand to convert it over in our marshal call.  
> 
> 
> Alex, do you think it would be a lot of work to extend it to handle
> this?  Is it worth looking into?

Its sort of hard to recursively handle any type of object. What i
imagined was more like creating a special type for your return object,
and then have a marshaller for that type.

So, you'd have:
class MessageList extends Vector implements XmlRpcMarshaller {
...

  Object marshal(Object object, XmlRpcHandler handler) {
     // do stuff
  }
}

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 Alexander Larsson                                            Red Hat, Inc 
                   alexl redhat com    alla lysator liu se 
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