Java RMI - UnicastRemoteObject: what is the difference between UnicastRemoteObject.exportObject() and extends UnicastRemoteObject?

Question

i\'m preparing for an exam and I\'m having a question that I hope someone here could answer me.

It\'s about RMI and remote objects. I wonder why there is so much differe

Answer 1

Firstly, binding & rebinding remote object using Naming class and Registry class is not relevant to scenarios of whether or not a class is extending UnicastRemoteObject. See here for the differences.

Secondly, the difference between the class extending UnicastRemoteObject is that if the object of that type is used as a stub, then you'll not need to call UnicastRemoteObject.exportObject to obtain the stub anymore for binding with registry. In your version 1, the StorehouseImpl must have extended the UnicastRemoteObject, and in fact, there's no need for EchoImpl to extend UnicastRemoteObject for your version 1 as there is no instance of EchoImpl is registered as a remote object to the registry.

Thirdly, you mention what'd happen if rebind is executed without bind is executed beforehand. As explained in the javadoc here, if no key name has been inserted, it will behave in the same way as if first time bind is executed.