RMI Interview Preparation Guide
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RMI Interview Questions and Answers will guide us now that the Java Remote Method Invocation API, or Java RMI, is a Java application programming interface that performs the object-oriented equivalent of remote procedure calls (RPC). So learn RMI or get preparation for the job of RMI by this Java Remote Method Invocation Interview Questions with Answers guide

21 RMI Questions and Answers:

1 :: What is Java RMI?

Remote Method Invocation (RMI) is the process of activating a method on a remotely running object. RMI offers location transparency in the sense that it gives the feel that a method is executed on a locally running object.

2 :: What are the layers of RMI Architecture?

The RMI is built on three layers.
a. Stub and Skeleton layer
This layer lies just beneath the view of the developer. This layer intercepts method calls made by the client to the interface reference variable and redirects these calls to a remote RMI service.

b. Remote Reference Layer.
This layer understands how to interpret and manage references made from clients to the remote service objects. The connection is a one-to-one (unicast) link.

c. Transport layer
This layer is based on TCP/IP connections between machines in a network. It provides basic connectivity, as well as some firewall penetration strategies.

3 :: What is the basic principle of RMI architecture?

The RMI architecture is based on one important principle: the definition of behavior and the implementation of that behavior are separate concepts. RMI allows the code that defines the behavior and the code that implements the behavior to remain separate and to run on separate JVMs.

4 :: How many types of protocol implementations does RMI have?

RMI has at least three protocol implementations:
Java Remote Method Protocol(JRMP), Internet Inter ORB Protocol(IIOP), and Jini Extensible Remote Invocation(JERI). These are alternatives, not part of the same thing, All three are indeed layer 6 protocols for those who are still speaking OSI reference model.

5 :: Does RMI-IIOP support dynamic downloading of classes?

No, RMI-IIOP doesn't support dynamic downloading of the classes as it is done with CORBA in DII (Dynamic Interface Invocation).Actually RMI-IIOP combines the usability of Java Remote Method Invocation (RMI) with the interoperability of the Internet Inter-ORB Protocol (IIOP).So in order to attain this interoperability between RMI and CORBA,some of the features that are supported by RMI but not CORBA and vice versa are eliminated from the RMI-IIOP specification.

7 :: What is the role of Remote Interface in RMI?

The Remote interface serves to identify interfaces whose methods may be invoked from a non-local virtual machine. Any object that is a remote object must directly or indirectly implement this interface. Methods that are to be invoked remotely must be identified in Remote Interface. All Remote methods should throw RemoteException.

8 :: What is the role java.rmi.Naming Class?

The Naming class provides methods for storing and obtaining references to remote objects in the remote object registry.

9 :: What is the default port used by RMI Registry?


10 :: What is meant by binding in RMI?

Binding is a process of associating or registering a name for a remote object that can be used at a later time to look up that remote object. A remote object can be associated with a name using the Naming class's bind or rebind methods.