XML Hacks

Process XML Documents with XSL-FO and FOP

Use Apache’s FOP engine together with XSL-FO to generate PDF output.

Apache’s FOP or Formatting Objects Processor (http://xml.apache.org/fop/) is an open source Java application that reads an XSL-FO (http://www.w3.org/TR/xsl/) tree and renders the result primarily as PDF. However, other formats are possible, including Printer Control Language (PCL), PostScript (PS), Scalable Vector Graphics (SVG), an area tree representation of XML, Java Abstract Windows Toolkit (AWT), FrameMaker’s Maker Interchange Format (MIF), and text.

XSL-FO defines formatting objects that help describe blocks, paragraphs, pages, tables, and so on. These formatting objects are aided by a large set of formatting properties that control fonts, text alignment, spacing, etc., many of which match the properties used in CSS (http://www.w3.org/Style/CSS/). XSL-FO’s formatting objects and properties provide a framework for creating attractive, printable pages.

XSL-FO is a huge, richly detailed XML vocabulary for formatting documents for presentation. XSL-FO is the common name for the XSL specification produced by the W3C. The spec is nearly 400 pages long. At one time, XSL-FO and XSLT (whose finished spec is less than 100 pages) were part of the same specification, but split into two specs in April 1999. XSLT became a recommendation in November 1999, but XSL-FO did not achieve recommendation status until October 2001.

To get you started, we’ll go over a few simple examples. The ...