无法使用 PDFBox 将图像添加到 pdf

Question

I'm writing a java app that creates a pdf from scratch using the pdfbox library.
I need to place a jpg image in one of the page.

I'm using this code:

PDDocument document = new PDDocument();
PDPage page = new PDPage(PDPage.PAGE_SIZE_A4);
document.addPage(page); 
PDPageContentStream contentStream = new PDPageContentStream(document, page);

/* ... */ 
/* code to add some text to the page */
/* ... */

InputStream in = new FileInputStream(new File("c:/myimg.jpg"));
PDJpeg img = new PDJpeg(document, in);
contentStream.drawImage(img, 100, 700);
contentStream.close();
document.save("c:/mydoc.pdf");

When I run the code, it terminates successfully, but if I open the generated pdf file using Acrobat Reader, the page is completely white and the image is not placed in it.
The text instead is correctly placed in the page.

Any hint on how to put my image in the pdf?

Answer 1

Definitely add the page to the document. You'll want to do that, but I've also noticed that PDFBox won't write out the image if you create the PDPageContentStream BEFORE the PDJpeg. It's unexplained why this is so, but if you look close at the source of ImageToPDF that's what they do. Create the PDPageContentStream after PDJpeg and it magically works.

...
PDJpeg img = new PDJpeg(document, in);
PDPageContentStream stream = new PDPageContentStream( doc, page );
...

Answer 2

Looks like you're missing just a document.addPage(page) call.

See also the ImageToPDF example class in PDFBox for some sample code.

Answer 3

this is how default constructor for PDPageContentStream looks like:

public PDPageContentStream(PDDocument document, PDPage sourcePage) throws IOException
{
    this(document, sourcePage, AppendMode.OVERWRITE, true, false);
}

Problem is AppendMode.OVERWRITE for me using another constructor with parameter PDPageContentStream.AppendMode.APPEND resolved a problem

For me this worked:

PDPageContentStream contentStream =
        new PDPageContentStream(document, page, PDPageContentStream.AppendMode.APPEND, true, false);