Footer image printed twice when printing certificates in iText - itext

Question

When we print certificate all most print in certificate but footer image is printing twice. I am using Pdfptable for printing footer image.
table = new PdfPTable(1);
int footerWidth[] = {100};
table.setWidths(footerWidth);
table.setWidthPercentage(100);
Image image2 = Image.getInstance("footerImage.jpg");
cell = new PdfPCell(image2,true);
cell.setBorder(0);
table.setTotalWidth(document.getPageSize().width()-document.leftMargin()-document.rightMargin());
table.addCell(cell);
//write the footer
table.writeSelectedRows(0, -1, document.leftMargin(), table.getTotalHeight()+document.bottomMargin(), writer.getDirectContent());
EventLog.write(appName,"done adding footer",logFile);
document.add(table);

Answer 1

Your table is added twice because you add it twice.
You add it a first time when you use writeSelectedRows():
table.writeSelectedRows(0, -1, document.leftMargin(), table.getTotalHeight()+document.bottomMargin(), writer.getDirectContent());
This adds the table at a very specific position defined by the coordinates:
x = document.leftMargin();
y = table.getTotalHeight()+document.bottomMargin();
You add the table a second time, when you do this:
document.add(table);
This adds the table at whichever position the page cursor is at, which is usually immediately after the previous content that was added with a document.add() method.
PS:
Headers and footers are usually added in an OnEndPage() page event. You're adding the footer only once. You may want to use page events to add the footer on every page.