IBM Version 5 manual XSL debugger, XPath Query Result screen

Figure 5-13 XPath Query Result screen

5.5 XSL debugger

This tool enables you to visually step through an XSL transformation script, highlighting the transformation rules as they are fired. It is used to test the generated XSL style sheet. Simply use the editor to apply the XSL style sheet to a source XML file, and create a new HTML or XML file. You can then trace through the new XML or HTML file to verify if the results are correct.

The XSL trace editor only works on a one-to-one basis. You can only apply an XSL file to one XML file at a time if you want to use the XSL trace editor to trace through the results. As well, you cannot apply as XSL file that references another XSL file to an XML file, and trace the results.

So, to invoke the XSL debugging process, select your XML file to be transformed, and XSL file in the Navigator view, then invoke the trace from the context menu by selecting Apply XSL—>As HTML. The trace editor presents the input XML, and the input XSL, as shown in Figure 5-14. You can replay the transform using stepping controls in the toolbar. As the transform is applied, the trace editor highlights each XSL statement, and the XML input element it matches, allowing you to understand and resolve any problems.

96 The XML Files: Development of XML/XSL Applications Using WebSphere Studio