public static PDTrueTypeFont prepareFont(PDDocument _pdfDocument) throws IOException
    {
        InputStream fontStream = new FileInputStream(new File("/home/lightsoft/bonprix/hk-grotesk/HKGrotesk-Bold.ttf"));
        return PDTrueTypeFont.loadTTF(_pdfDocument, fontStream);
    }

use :       PDTrueTypeFont pdTrueTypeFont = prepareFont(finalDoc);