NonStop Systems Introduction

The Application Server Environment
NonStop Systems Introduction—527825-001
3-21
NonStop CORBA
these tasks are all handled by the CORBA software. Developers simply call the
appropriate functions.
CORBA provides many benefits, including:
•
Coexistence with existing systems. Legacy applications can be encapsulate in a
C++ or Java “wrapper” that defines a CORBA-compliant interface to the legacy
code. This enables the legacy applications to interoperate with new applications,
thus protecting your investment in existing systems.
•
CORBA-compliant software objects are fully interoperable, even when they are
developed by different vendors who have no knowledge of each other’s objects.
•
CORBA-compliant objects are portable and can easily be moved from one platform
to another.
Figure 3-14 on page 3-21 shows a simplified diagram of the CORBA architecture.
As the figure shows, communications between clients and objects are handled by the
ORB.
CORBA objects in a heterogeneous network can communicate over the internet using
the Internet Inter-ORB Protocol (IIOP). Using IIOP, developers can write programs that
can communicate with other programs wherever they are located and without having to
understand anything about the programs other than their services and names.
CORBA servers are written in C, C++, or Java. Developers use a standard CORBA
specification called the Interface Definition Language (IDL) to define the program
Figure 3-14. Basic CORBA Architecture
Application
client
Application
objects
ORB- provided
services
! Naming service
! Event service
! Transaction service
vst030.vsd
Request
Object Request Broker (ORB)