How does it read data from the PDF? Is there a PDF parser somewhere down inside the code?
Unfortunately it looks like the developers of JPedal decided to discontinue the LGPL version and focus on the proprietary version, so it's unmaintained unless someone else picks up development.
We use JPedal for rendering pages as images. For parsing, we use Apache PDFBox. In the near future, we plan to render the PDFs client side with Mozilla's PDF.js
Moving to PDFBox 2.0 is also on our roadmap. But the text extraction API in 2.0 has changed a lot too, so porting our engine would require quite a bit of effort.
Friendly reminder: we're an MIT-licensed open source project, and we're always open to contributions!