PDFBox 2.0.27: Watermarking with map for page specific overlay files results in no watermark-CodePudding

Background information

I am using PDFBox 2.0.27 and try to add watermarks on my PDF (may) containing multiple pages of different Din formats and orientations (vertical & horizontal).

For this reason I created for each combination of Din format and orientation a PDF file, which I want to utilize for watermarks of the respective pages of my original PDF.

Approach

The specific page and overlay/watermark file relation is stored in HashMap<Integer, String> overlayGuide = new HashMap<>();

For adding watermarks to each page I use the following code:

PDDocument originalPDF = PDDocument.load(new File("..Original_PDF.pdf"));   // To adjust with actual path

HashMap<Integer, String> overlayGuide = new HashMap<>();
overlayGuide.put(1, "..A1_Horizontal_Watermark.pdf");   // To adjust with actual path

Overlay overlay = new Overlay();
overlay.setInputPDF(originalPDF);
overlay.setOverlayPosition(Overlay.Position.BACKGROUND);
originalPDF = overlay.overlay(overlayGuide);

originalPDF.save(new File("C:\\AxaviaPdfServiceAPI\\temp\\watermarked.pdf"));

overlay.close();

Source of code snippet

This code is based on the suggested code from here.

Problem

The watermarking doesn't work. The output generated by the above code is the original PDF. I receive no exceptions or errors or other hints I could deliver.

What am I missing? The method overlay.setOutputFile("final.pdf"); as posted in the linked stackoverflow question is not available in my currently used version of PDFBox.

Size and orientation of page from original PDF and watermark PDF is (/should be) the same. Manual adding of watermark via Adobe Acrobat DC is working.

Expected result

Based on manual adding via Adobe Acrobat DC I expected something like here

Unfortunatelly I couldn't find an option in Overlay class to set opacity for the watermark PDF to add.

What I tried

See code snippet above & googeling, which resulted in more or less the same code snippet. Other solutions only handled simple text as watermark or images.

Example files

Example files to test my code can be found here

Boundary conditions

I want to stick at template PDFs for watermarking, since I want to add additional icons/pictures. The provided example file is just a short draft.

Update 2022-11-06

Please share both the input and the output PDFs of your test. – mkl

Original PDF: here

Watermark PDF: here

Result PDF: here

Any help is appreciated. Thank you in advance.

CodePudding user response：

Thanks to mkl for pointing out, that the approach with HashMap<Integer, String> overlayGuide = new HashMap<>(); is currently bugged.

Solution/Work-around

I used the method overlay.overlayDocuments(overlayGuidePDDocuments); with overlayGuidePDDocuments = HashMap<Integer, PDDocument> and the watermarks are now set correctly.

Remarks

Setting an opacity for the watermark template PDFs is not possible (or I don't get it how to apply). Therefore the watermark template PDFs are prepared with an opacity.