In Jini service discovery, you can search for all types of services by providing null for the class[] of service types to discover. My question is what happens if you don't have in your classpath the discovered service interface. For example, in the network there are 2 service with the interfaces IService1 and IService2, both not in my classpath. What would happen when they are discovered? will the code be downloaded to my JVM from the HTTP server (assuming it is configured to point to the HTTP server)?
(yeah, I know Jini is pretty dead :-))
Thanks!
What you probably refer to is service lookup. From the spec: "The lookup service provides a central registry of services available within the djinn. This lookup service is a primary means for programs to find services within the djinn..." As for disccovery: "Entities that wish to start participating in a distributed system of JiniTM technology-enabled services and/or devices, known as a djinn, must first obtain references to one or more Jini lookup services. The protocols that govern the acquisition of these references are known as the discovery protocols."
I think you have to know your types you want to use. What are you going to do with an interface you know no nothing about? When you know the interface and what it is good for, you build your program relying on it. What you get in Jini by a service lookup is an implementation of that service interface.
I am aware my answer is sketchy. I would like to direct you to the place where Jini continues its existence: river.apache.org. Jini is live and well! Use the specifications, examples and of course the mailing lists to get an exhaustive answer. Cheers.