I'm reviewing PDF generation tools available for Java and haven't found much of the examples.
The best for FOP so far was the documentation linked in this question.
For the iText the best I had found are the Advanced Aquarist magazine samples for 2008.
Unfortunately for both cases there are no sources. As I have some background with iText, the Aquarist seems to be reaching iText's maximum in this sample. Is there anything like this for FOP?