how to invoke extern operation when publishing advertisement

Hi ,every expert in jxta,
   I have a question to ask you , this question is about how to expand the
function of jxta. Now I want to implement the distributed uddi based the p2p
platform ¨Cjxta. Because my distributed uddi is based on p2p, so when the
communication between these uddi registers is based on jxta platform, when I
publish a advertisement in jxta ,I can send a misson publish(adv) or
remotepublish(adv), when other remote peers received the publish request, the peer
will publish the advertisement in the node ,but at this time I want to spring the
operation on publishing service in uddi register. But I do not know how to spring
other operation, Because the remotepublish¡¯s code is implemented by invoking
other¡¯s source code, and I do not know the detail about the inside invoking
relation between the source code.
   If you have do the same expand as me ,please tell me which¡¯s source method
code is responsible for adding the extern operation. Thanks a lot.
                                          
                                             shiny