title: PDFBox: FDFDocument not imported
body: <p>I'm trying to copy FDFDocument from one pdf to another. Here's how I'm trying to do it:</p>
  
  <pre><code>  try (PDDocument document = PDDocument.load(new File("C:\\Users\\fdf\\dummyPdf1.pdf"))) {
  
    PDAcroForm acroForm = document.getDocumentCatalog().getAcroForm();
    FDFDocument fdfDocument = acroForm.exportFDF();
  
    PDDocument dummyDocument = PDDocument.load(new File("C:\\Users\\fdf\\dummyPdf2.pdf"));
    dummyDocument.getDocumentCatalog().getAcroForm().importFDF(fdfDocument);
  
    dummyDocument.save("C:\\Users\\fdf\\dummyPdf3.pdf");
    dummyDocument.close();
  }
  </code></pre>
  
  <p>I'm hoping to copy all the form fields that are configured in testPdf to dummyPdf. But, I don't see the form fields are being copied. What am I missing here? is there any other approach to what I need? I'm using <code>2.0.9</code> version of pdfbox if that helps.</p>
  
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