Rexx Programmer's Reference

Chapter 18. XML and Other Interfaces

Overview

There are more free and open-source Rexx interfaces and tools than one book can possibly cover, so this book just introduces a few of the most popular. This chapter describes XML programming with a package called RexxXML. It tells how to write scripts that manipulate XML and HTML data files and how to accomplish other XML-related tasks.

To start, we'll define what XML is, and what related terms like XSLT, XPath, and HTML mean. Then we'll look at the kinds of processing you can accomplish using the RexxXML package. After that, we'll briefly discuss the functions in RexxXML, including those for document tree parsing, document tree searching, XSLT processing, and schema validation. After we discuss how to download and install RexxXML, we'll illustrate specific XML operations, such as how to load and process XML documents, how to process documents, how to validate documents, and how to process them against an XSLT stylesheet. With this background, we'll review a script that uses RexxXML to read a Web page, identify a specific data element within that Web page, and compare the value of the data element to the version of RexxXML used within the script. The script uses the Web page to determine if a more recent version of RexxXML is available than the user has installed.

The chapter concludes by mentioning many other free and open-source Rexx tools, packages, and interfaces. Most can be found on the Web and freely downloaded just by entering their ...