I think this is exactly what you were looking for
http://today.java.net/pub/a/today/2007/06/26/generating-pdfs-with-flying-saucer-and-itext.html
http://code.google.com/p/flying-saucer
Flying Saucer’s primary purpose is to render spec-compliant XHTML and CSS 2.1 to the screen as a Swing component. Though it was originally intended for embedding markup into desktop applications (things like the iTunes Music Store), Flying Saucer has been extended work with iText as well. This makes it very easy to render XHTML to PDFs, as well as to images and to the screen. Flying Saucer requires Java 1.4 or higher.