Ok, after about 7-8 days of debugging, I've finally figured out what's
going on with my RMI problem, but I don't know how to fix it. The root
of the problem is whenever a remote object (i.e., a stub) is gets
serialized and then deserialized, the object is unusable because it
doesn't have a delegate set (via _set_delegate()). During
serialization, the code in RMIStubHandler.stubWriteReplace() replaces
the serialized Stub with an instance of RMIPersistentStub.
RMIPersistentStub does a _set_delegate(stub._get_delegate()) to
initialize with the same delegate value.
During deserialization, RMIPersistentStub calls
result = javax.rmi.PortableRemoteObject.narrow(this, type);
to activate the object. But this fails because the stub _get_delegate()
throws an exception because no delegate has been set. After much
digging, and head scratching, I finally figured out why the delegate is
null. The delegate field in the ObjectImpl superclass is transient! So
when this object is serialized and then deserialized, the connection to
the original object is lost. I've checked against the Sun
implementation, and it appears that field is marked transient there
too. So, I'm guessing RMIPersistentStub needs to pass the delegate
information via some other means that will survive the serialization
process. Does anybody have any suggestions on what the appropriate fix
would be?
Rick
