merge files gives error: End-of-File, expected line

Question

I'm Using PdfBox for android in order to append data to a PDF file.

The data to append

public byte [] prerparePdfToAppend() {

    final PDDocument document = new PDDocument();
    final PDPage sourcePage = new PDPage();
    document.addPage(sourcePage);

    PDPageContentStream contentStream = new PDPageContentStream(document, sourcePage);
    contentStream.beginText();
    contentStream.setFont(PDType1Font.COURIER, 12);
    contentStream.showText("Name: " + firstName + " " + lastName);
    contentStream.newLine();
    ...
    contentStream.endText();
    contentStream.close();

    output = new ByteArrayOutputStream();
    document.save(output);
    document.close();
    byte [] bytesToAppend = new byte[output.size()];
    output.write(bytes);
    output.close();

    return bytesToAppend;
}

Merge Code (simplified)

public void merge (String assetFileName) {
    byte [] toAppendPdf = prerparePdfToAppend();
    PDFMergerUtility mergerUtility = new PDFMergerUtility();
    mergerUtility.addSource(PDFBoxResourceLoader.getStream(assetFileName));
    mergerUtility.addSource(new ByteArrayInputStream(toAppendPdf));
    mergerUtility.setDestinationStream(destStream);
    mergerUtility.mergeDocuments(); //IOException
}

The Exception

java.io.IOException: Error: End-of-File, expected line
   at org.apache.pdfbox.pdfparser.BaseParser.readLine(BaseParser.java:1419)
   at org.apache.pdfbox.pdfparser.COSParser.parseHeader(COSParser.java:1648)
   at org.apache.pdfbox.pdfparser.COSParser.parsePDFHeader(COSParser.java:1627)
   at org.apache.pdfbox.pdfparser.PDFParser.parse(PDFParser.java:348)
   at org.apache.pdfbox.pdmodel.PDDocument.load(PDDocument.java:888)
   at org.apache.pdfbox.pdmodel.PDDocument.load(PDDocument.java:802)
   at org.apache.pdfbox.multipdf.PDFMergerUtility.mergeDocuments(PDFMergerUtility.java:172)

Answer 1

The last lines of the prerparePdfToAppend method look weird to me. But why make your life complicated? Return a PDDocument:

public PDDocument prerparePdfToAppend()
{
    final PDDocument document = new PDDocument();
    final PDPage sourcePage = new PDPage();
    document.addPage(sourcePage);

    PDPageContentStream contentStream = new PDPageContentStream(document, sourcePage);
    contentStream.beginText();
    contentStream.setFont(PDType1Font.COURIER, 12);
    contentStream.showText("Name: " + firstName + " " + lastName);
    contentStream.newLine();
    ...
    contentStream.endText();
    contentStream.close();

    return document;
}

Your merge code would then look like this:

public void merge (String assetFileName)
{
    PDFMergerUtility mergerUtility = new PDFMergerUtility();
    PDDocument srcDoc = PDDocument.load(PDFBoxResourceLoader.getStream(assetFileName));
    PDDocument dstDoc = prerparePdfToAppend();
    mergerUtility.appendDocument(dstDoc, srcDoc);
    dstDoc.save(destStream);
    srcDoc.close();
    dstDoc.close();
}

If this doesn't work - make sure that

PDFBoxResourceLoader.getStream(assetFileName)

is really the stream of a real PDF. If it still doesn't work, mention which line of this new code produces the exception. And of course, make sure you're using the latest version of PDFBox.