Can I use RMI to find an object with contructor with params?

Question

Does an RMI available object HAVE to be a parameter-less constructor?
All the examples I see are:
MyClass mc = (MyClass) Naming.lookup("/HelloServer");
Is there any way to pass arguments to its constructor?

Answer 1

RMI client invokes a remote method on the server object through proxy stub of the server object obtained via Naming service. Stub implements all remote interfaces exported by the RMI server object which basically marshals all the parameters of the remote method, sends the method request to server object skeleton residing in a different address space via TCP connection and finally receives the result from the server object if any, unmarshals and returns result to the caller.
Server side RMI appilcation instantiates the RMI server class which implements all intended remote interfaces, exports it to the RMI runtime and finally registers itself with Naming service. RMI client only obtains a reference to the RMI server object through lookup method of the Naming service. Remember client does not instantiate a server object, client only knows about the remote interface implemented by the server object and does not have any idea about its implementation object details. On the server sice the Class which implements remote interfaces, can pass any number of arguments to its constructor.
In your example, MyClass is the stub to the remote server object which implements "MyClass" remote interface. The stub only provides boiler-plate code for remote methods which marshalls params, sends request to RMI server object, receives the result object, unmarshals it and finally returns it to the caller. The stub only contains the necessary information details like remote object ID, host and port to contact the RMI server object which implements the remote interface.
So client does not instantiate a server implementation objet, it only obtains a reference (stub) to the server object thru Naming service. Remote interface implementation object can declare a constructor which takes any number of arguments. RMI server side application only instantiates this implementation object and registers its stub with the Naming service.
-- Srinath Mandalapu