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underlying business logic.

When XML is used as envisioned, all data, both of type character and numeric are

represented as printable text, completely divorced from any platform-specific

representation or encoding. The net effect is that two entities or programs can interact

without having to know the data structures that comprise each other's binary interface.

Of course, the XML that is exchanged cannot be arbitrary, so industry standards such as

XML Schema (XSD) [39], [40] and Web Services Definition Language (WSDL) [41],

[42] were developed. XML Schema is used to formally describe XML documents, while

WSDL is used to describe services and the operations they support. Operations in Web

services are akin to public methods in the object-oriented programming paradigm. A

Web service is considered to be WS-I compliant [43], or generally interoperable, if it

meets many criteria, not the least of which is using XML documents for the input and

output of each operation. There are many criteria defined by WS-I that apply to a Web

service definition, but this particular facet, where XML is the interoperable interface of

choice, sets the stage for a meaningful exercise where the focus is on the activity of

making a component from a COBOL program that is reusable from Java using XML in a

light-weight, local environment.

In recent history, the ability to parse and generate XML documents has been

added to the COBOL language in many implementations including the Micro Focus and

IBM COBOL compilers and runtimes [37], [44]. XML parsing in COBOL is

accomplished through the use of the XML PARSE statement, which performs an event-


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