IText merge tagged pdf - Rebuild failed: trailer not found.; Original message: PDF startxref not found

Question

We use iText version 5.5 PdfCopy to merge multiple tagged PDFs. (Those tagged PDFs are not created by iText.) We got the following error while document.close:

java.lang.NullPointerException
at com.itextpdf.text.pdf.RefKey.<init>(RefKey.java:59)
at com.itextpdf.text.pdf.PdfCopy.fixTaggedStructure(PdfCopy.java:822)
at com.itextpdf.text.pdf.PdfCopy.flushTaggedObjects(PdfCopy.java:779)
at com.itextpdf.text.pdf.PdfDocument.close(PdfDocument.java:854)
at com.itextpdf.text.Document.close(Document.java:416)
com.itextpdf.text.exceptions.InvalidPdfException: Rebuild failed: trailer not found.;    Original    message: PDF startxref not found.
at com.itextpdf.text.pdf.PdfReader.readPdf(PdfReader.java:668)
at com.itextpdf.text.pdf.PdfReader.<init>(PdfReader.java:181)
at com.itextpdf.text.pdf.PdfReader.<init>(PdfReader.java:230)
at com.itextpdf.text.pdf.PdfReader.<init>(PdfReader.java:207)
at com.itextpdf.text.pdf.PdfReader.<init>(PdfReader.java:197)

PDF are valid and contains trailer and %EOF, Files are not corrupted. What other could cause this?

Answer 1

You may have found the answer already. I had the same issue and I solved it by closing the document before instantiating PdfReader.

Example:

**

Document tempDoc = new Document(PageSize.A4, 40, 40, 80, 20);
ByteArrayOutputStream tempBaos = new ByteArrayOutputStream();   
PdfWriter.getInstance(tempDoc, tempBaos);
tempDoc.open();

tempDoc.add(tempChap);
tempDoc.close();    // Closing the document before calling Reader

PdfReader reader = new PdfReader(tempBaos.toByteArray());

**

Hope this will help