XSLT Summary

In the previous sections, we have shown how XSLT can be used to create sophisticated webs from XML data stored in Tamino. However, we have also encountered some of the limitations of XSLT. Let us summarize the advantages and disadvantages of this technology:

Advantages

  • XSLT processors are readily available on various platforms. Processors like XT, Saxon and XALAN are implemented in Java and run on any server. On Windows platforms, the MSXML DLL provides adequate support.

  • An XSLT stylesheet can convert XML into almost any output format, from HTML over XHTML to WML, SVG, SMIL, etc. This allows support not only for HTML clients but also for mobile clients and multimedia applications.

  • With the help of serialization and the XSLT server extension, XSLT stylesheets allow Tamino to deliver query results in customized formats.

Disadvantages

  • Processing XSLT stylesheets consumes considerable CPU resources. Scalable applications often require a cache for transformation results in order to achieve the necessary throughput. Another throughput-enhancing option is the use of an XSLT compiler, for example the XSLT compiler contained in XALAN, which translates an XSLT stylesheet into a set of Java classes.

  • XSLT does not provide a binding between the original XML document and the result of the transformation. Insert, update and delete operations require additional program logic.

  • The XSLT standard has some limitations. Advanced transformations require the use of extensions (see section Limitations of XSLT).

  • The XSLT syntax is hard to read, and rule-based programming is a concept alien to many programmers.

  • WYSIWYG design of XSLT-generated HTML pages is possible with tools such as eXcelon's Stylus, Whitehill's XSL Composer and XML Spy Suite. However, such tools are not commonly used by most web designers.