| It should come as no surprise to someone reading this foreword that two of the most
influential forces in information systems over the last few years have been Java and
XML. Java provides a stable, industrial-strength language that runs on a variety of
platforms, while XML offers a simple format for the exchange of information across
a variety of platforms.Together, they showcase tools for developing numerous applications:
from reaching back into legacy computer systems, to reaching out to users
and partners on the World Wide Web.
Lately, it has become popular to combine these two technologies in a highly-distributed
architectural technique called Web services. Broadly speaking, a Web service is
the exposure of a business process over a network.The connotation is generally that
XML-based traffic is being moved on a public network (the Internet) via the HTTP
protocol. However,Web services can also be useful internally to an organization, as a
mechanism for encapsulating and exposing the business logic inherent in legacy systems.
New applications can then utilize this Web service interface to leverage the
complex business logic that has been refined, sometimes for decades, in these legacy
systems.This allows for the reuse of systems at the logical level, without regard to
physical configuration. |
