How to add Code128 Barcode image to existing pdf using pdfbox(1.8.12) with barcode4j library? - pdfbox

Question

I am trying to generate the barcode from barcode4j library(code128bean, other barcode beans) and try to add to the existing pdf. The barcode image is getting created locally using the below code.
//Create the barcode bean
Code128Bean code128Bean = new Code128Bean();
final int dpi = 150;
code128Bean.setModuleWidth(UnitConv.in2mm(1.0f / dpi)); //makes the narrow bar
//width exactly one pixel
//bean.setCodeset(2);
code128Bean.doQuietZone(false);
//Open output file
File outputFile = new File("D:/barcode4jcod128.png"); //I dont want to create it
OutputStream code128Stream = new FileOutputStream(outputFile);
try {
//Set up the canvas provider for monochrome PNG output
BitmapCanvasProvider canvas1 = new BitmapCanvasProvider(
code128Stream, "image/x-png", dpi, BufferedImage.TYPE_BYTE_BINARY, false, 0);
//Generate the barcode
code128Bean.generateBarcode(canvas1, "123456");
//Signal end of generation
canvas1.finish();
} finally {
code128Stream.close();
}
My problem is I don't want to create an image and save it locally in filesystem and then add it as image to pdf. I just want to create dynamically i mean just create the barcode image dynamically and add it to the pdf.
How do I set the pagesize (like PDPage.PAGE_SIZE_A4) to the existing PDPages which I retrieved from catalog.getAllPages() method, like (List<PDPage> pages = catalog.getAllPages();)
Can somebody help on this?
Thank you so much for your help Tilman. Here is what i did
public static BufferedImage geBufferedImageForCode128Bean(String barcodeString) {
Code128Bean code128Bean = new Code128Bean();
final int dpi = 150;
code128Bean.setModuleWidth(UnitConv.in2mm(1.0f / dpi)); //makes the narrow bar
code128Bean.doQuietZone(false);
BitmapCanvasProvider canvas1 = new BitmapCanvasProvider(
dpi, BufferedImage.TYPE_BYTE_BINARY, false, 0
);
//Generate the barcode
code128Bean.generateBarcode(canvas1, barcodeString);
return canvas1.getBufferedImage();
}
// main code
PDDocument finalDoc = new PDDocument();
BufferedImage bufferedImage = geBufferedImageForCode128Bean("12345");
PDXObjectImage pdImage = new PDPixelMap(doc, bufferedImage);
PDPageContentStream contentStream = new PDPageContentStream(
finalDoc, pdPage, true, true, true
);
contentStream.drawXObject(pdImage, 100, 600, 50, 20);
contentStream.close();
finalDoc.addPage(pdPage);
finalDoc.save(new File("D:/Test75.pdf"));
The barcode is getting created the but it is created in vertical manner. i would like to see in horizontal manner. Thanks again for your help.

Answer 1

1) add an image to an existing page while keeping the content:
BitmapCanvasProvider canvas1 = new BitmapCanvasProvider(
dpi, BufferedImage.TYPE_BYTE_BINARY, false, 0
);
code128Bean.generateBarcode(canvas1, "123456");
canvas1.finish();
BufferedImage bim = canvas1.getBufferedImage();
PDXObjectImage img = new PDPixelMap(doc, bim);
PDPageContentStream contents = new PDPageContentStream(doc, page, true, true, true);
contents.drawXObject(img, 100, 600, bim.getWidth(), bim.getHeight());
contents.close();
2) set the media box to A4 on an existing page:
page.setMediaBox(PDPage.PAGE_SIZE_A4);