... generating PDF files using another PDF as a template. The new PDF has to replace certain text fields from the template (based on their name) with data extracted from other sources.
The idea is to let the end user generate their own templates using any PDF editing program and asking him/her to name the fields that have to be replaced dynamically following a specification.
In general it's hard to impossible to alter text in a PDF. It may be possible if the text is part of an AcroForm. If it is, then the iText library can do that.
I was affraid that was the response. But after looking a little more into forms I think they might be suitable for what I need to do. And it looks quite simple to be done in iText.