This is how java use CORBA and RMI to develop distributed application.

1. Distributed Application
● Those Application which are run in Network and
communicate with other application.
● eg. Flight Booking Site, Weather forecasting
sites etc.

2. Problem
Flight Booking

3. CORBA

4. What is CORBA ?
● An Common Object Request Broker Architecture (CORBA) is a
standard defined by the Object Management Group (OMG)
designed to facilitate the communication of systems that are
deployed on diverse platforms.
● CORBA enables collaboration between systems on different
operating systems, programming languages, and computing
hardware.
● Using the standard protocol IIOP

5. ● CORBA uses an interface definition language (IDL) to specify the interfaces
that objects present to the outer world.
● CORBA then specifies a mapping from IDL to a specific implementation
language like C++ or Java.
● CORBA is world’s leading middleware solution enabling exchange of
information, independent of hardware platform and programming language.
Src: https://en.wikipedia.org/wiki/Common_Object_Request_Broker_Architecture

6. Working Mechanism
CORBA
Program A
. Run on window
. Written in Java
Program B
. Run on linux
. Written in C++
Img src:https://pngtree.com/free-icon/node-other-server_1247326

7. ● CORBA defines the Interface Design
Language(IDL).
● This allow client/server interaction with specific
implementation of Object Request
Broker(ORB).
● Best example of CORBA/AJAX tech is Esewa .

8. Architecture
Img src: https://www.youtube.com/watch?v=coQAvsrHwkw

9. Java RMI

10. Remote Method Invocation
● The RMI (Remote Method Invocation) is an API that provides a
mechanism to create distributed application in java.
● The RMI allows an object to invoke methods on an object
running in another JVM.
● The RMI provides remote communication between the
applications using two objects
1) Stub
2) Skeleton

11. Stub
● The stub is an object, acts as a gateway for the
client side.
● It resides at the client side and represents the
remote object.

12. it does the following tasks:
● It initiates a connection with remote Virtual Machine (JVM),
● It writes and transmits (marshals) the parameters to the remote
Virtual Machine (JVM),
● It waits for the result
● It reads (unmarshals) the return value or exception, and
● It finally, returns the value to the caller

13. skeleton
● The skeleton is an object, acts as a gateway for the server side
object.
● it does the following tasks:
1) It reads the parameter for the remote method
2) It invokes the method on the actual remote object, and
3) It writes and transmits (marshals) the result to the caller.
Src: https://www.javatpoint.com/RMI

14. Architecture
Img src: https://www.youtube.com/watch?v=coQAvsrHwkw

15. Summary
● Hence, distributed system is those system
which are running on web and communicate
with each other using middleware services like
COBRA,RMI,JSON,XML(AJAX).