NonStop Server for Java 7.0 Programmer's Reference

5 Java infrastructure

Java - WORA

Applications written in Java, as is well known, are platform agnostic. The platform specific features

are implemented by the Java Virtual Machine (JVM) thus insulating applications from platform

idiosyncrasies. Thus Java applications exhibit similar behavior even when run on different software

platforms. This is a unique feature of Java and is popularly called Write Once Run Anywhere

(WORA).

NonStop TS/MP: A scalable middleware platform on NonStop

NonStop provides a middleware platform in the form of NonStop TS/MP that provides applications,

NonStop characteristic features such as scalability and fault tolerance. NonStop TS/MP provides

all the necessary infrastructure that allows you to develop and deploy mission-critical online

transaction processing (OLTP) applications on NonStop servers. This helps you to concentrate on

implementing business logic, without being concerned with common application services such as

load balancing, communications, I/O, and fault tolerance. These common services are provided

by NonStop TS/MP, comprising a run time execution environment and a set of APIs. Applications

hosted on NonStop TS/MP must use NonStop File System (FS) and Pathsend API to inherit the

unique features of NonStop TS/MP. These APIs provide function calls that are used by the client

and server applications for Inter Process Communication (IPC).

Java infrastructure

Java Infrastructure provides Java abstraction to NonStop FS and TS/MP API that would enable

programmers to use Socket class in the java.net package or the SocketChannel in the

java.nio package to write NonStop TS/MP or standalone server applications without having

to use any FS or Pathsend API. With this a programmer can use plain sockets or any package that

use sockets for communication to write server applications and host the application on NonStop

TS/MP and inherit the unique features of NonStop TS/MP.

Such programs can be developed and tested on a desktop environment and deployed on NonStop

TS/MP to inherit the platform features. The subsequent sections help you to understand the

functionality of JI in detail. However, the actual operations related to connections in JI are discussed

in the section “Establishing a connection” (page 79).

Figure 3 (page 72) illustrates client server application depicting TCP/IP and JI as two different

communication channels for client server communication.