[PDFBOX-5788] ID References changes when saving PDFs.

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 3.0.1 PDFBox, 3.0.2 PDFBox
• Assignee: Unassigned
• Reporter: Daniel Persson
• Created: 19/Mar/24 07:11
• Updated: 20/Mar/24 14:50

Description

 

private static void runPDF(String name) throws IOException, NoSuchAlgorithmException {
    PDDocument doc = Loader.loadPDF(new File(name));

    File tmpFile = File.createTempFile("tmp", ".pdf");
    doc.save(tmpFile);
    byte[] data = Files.readAllBytes(Paths.get(tmpFile.getAbsolutePath()));
    byte[] hash = MessageDigest.getInstance("SHA256").digest(data);
    System.out.println(encodeHexString(hash));

    File tmpFile2 = File.createTempFile("tmp", ".pdf");
    doc.save(tmpFile2);
    byte[] data2 = Files.readAllBytes(Paths.get(tmpFile2.getAbsolutePath()));
    byte[] hash2 = MessageDigest.getInstance("SHA256").digest(data2);
    System.out.println(encodeHexString(hash2));
} 

Not sure, this might be expected behavior but it makes my testing framework a bit less robust so I thought I'd report it here. In the newer versions 3.0.2 and 3.0.1 when you save a PDF the second time the reference ID's continue incrementing which means that the PDF stored the first time is not identical to the second time.

In my test case depending on what thread executes first there might be difference in the run and the expected result changes.

I've not seen this with 3.0.0 and earlier versions of PDFBox.