What is CORBA? Compare it with RMI.

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 Common Object request broker is used for communication between distributed and heterogeneous objects that are written by in java language are any other language. CORBA is developed by Object Management Group (OMG). OMG adopted the CORBA standard in 1990. This was followed by many revisions of CORBA architecture. CORBA is world's leading middleware solution enabling the exchange of information independent of hardware platform, programming language, and operating system. Middleware is a type of computer software that provides services to software applications beyond those available from the operating system. It makes easier for software developers to implement communication and input/output, so they can focus on the specific purpose of their application.

                                   OR,

 Common Object Request Broker Architecture (CORBA) :

It is the standard developed by the Object Management Group to provide interoperability among distributed objects. It is the world’s leading middleware solution. It enables the exchange of information, independent hardware platforms, programming languages and operating systems. It is often defined as a “software bus” because it is a software-based communication interface through which the objects are located and accessed.


The difference between COBRA & RMI are as follows:- 


COBRA

  • CORBA has an implementation for many languages.
  • It uses Interface Definition Language (IDL) to separate interface from implementation.
  • CORBA objects are not garbage collected because it is language independent and some languages like C++ do not support garbage collection.
  • CORBA does not support this code-sharing mechanism.
  • CORBA passes objects by reference.
  • CORBA is a peer-to-peer system.
  • CORBA uses Internet Inter-ORB Protocol as its underlying remoting protocol.
  • The responsibility of locating an object implementation falls on the Object Adapter either Basic Object Adapter or Portable Object Adapter.


RMI

  • RMI is a Java-specific technology.
  • It uses a Java interface for implementation.
  • RMI objects are garbage collected automatically.   
  • RMI programs can download new classes from remote JVMs.
  • RMI passes objects by remote reference or by value.
  • Java RMI is a server-centric model.
  • RMI uses the Java Remote Method Protocol as its underlying remoting protocol.
  • The responsibility of locating an object implementation falls on JVM.





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