A posting from David Tolpin announces the availability of the RenderX XEP Rendering Engine release 2.7 as an evaluation version. XEP is "an engine that converts XSL FO documents to a printable form (currently PDF or PostScript). It can be used as a component in applications that need to generate high quality printable documents from data represented in XML. XEP is a native-mode XSL FO processor: the whole procedure of calculating the layout of every page is performed inside, without recurring to any third-party formatting engines like nroff, TeX, or whatever else. Native mode processing gives you considerable advantages in flexibility and cross-platform portability." XEP version 2.7 now implements the last version of the W3C XSL specification, viz., the XSL Recommendation of October 15, 2001. It offers enhanced functionality, documentation reformatted in DocBook, and includes a stylesheet which converts XSL CR documents to the final XSL Recommendation.

From the XEP description:

XEP is written in Java, and runs on any system that supports Java 2 (JDK/JRE 1.2.1) and above; best performance is achieved with JDK/JRE 1.3 or later. XEP 2.7 will also run with JDK/JRE 1.1.8; but support for this obsolete version is likely to be dropped in forthcoming editions. XEP can also run with Microsoft Java VM. The commercial version of XEP includes a COM wrapper class that enables its use as a component in Microsoft COM architecture.

XEP 2.7 conforms to the following version of XSL: W3C Recommendation of October 15, 2001. It can take input from a file, a byte stream, or a parsed XML document (via industry-standard SAX1/SAX2 interfaces). Currently supported output formats include PDF and PostScript. The architecture of XEP is modular, therefore adding a new output format is relatively easy.

XEP builds an exact internal representation of page layouts and then outputs it to the desired media using only the simplest graphic primitives. Therefore, it is relatively easy to add more output formats to the system. Moreover, the internal layout representation can be output in an XML-based layout description format; this gives you an extra flexibility in storing / manipulating formatted documents. This format is documented in the commercial version, to give XEP's users a possibility to implement custom output handlers.