i creating a pdf document using itext and inserted the page numbers. the user take the soft copy and pdf document and insert a scanned page using acrobat writer. by the time the page number should be rearranged accordingly. but it not happen in my case. because i am writing the page number in pdf document using pdfstamper like

showTextAligned(PdfContentByte.ALIGN_LEFT, "Page " + i + " of " + n, x, 5, 0);

the code to write page number

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

            reader.makeRemoteNamedDestinationsLocal();

            baos = new ByteArrayOutputStream();

            PdfStamper stamper = new PdfStamper(reader, baos);

            BaseFont bf = BaseFont.createFont(BaseFont.HELVETICA,

                    BaseFont.CP1252, BaseFont.NOT_EMBEDDED);

            PdfContentByte cb;

            int n = reader.getNumberOfPages();

            for (int i = 1; i <= n; i++) {

                cb = stamper.getOverContent(i);

                float x = cb.getPdfDocument().getPageSize().getWidth() / 2;

             if (cb.getPdfDocument().getPageSize().equals(

                        PageSize.A4.rotate())) {

                    x = x + 150;

                }

             else if(cb.getPdfDocument().getPageSize().equals(

                        PageSize.A4)){

             //Condition to check if the page is rotated - If rotated then page number should be adjusted acc to the height    

                 if(reader.getPageRotation(i)==90){

                     x = cb.getPdfDocument().getPageSize().getHeight()/2 - 50;

                 }

                 else{

                    x = x - 50;

                 }

             }

                cb.beginText();

                cb.setFontAndSize(bf, 10);

                cb.showTextAligned(PdfContentByte.ALIGN_LEFT, "Page " + i

                        + " of " + n, x, 5, 0);

                cb.endText();

            }

            stamper.close();