var document = new Document();
      var writer = PdfWriter.getInstance(document, outputBuffer);
      // step 2: open the document
      document.open();
      document.setMargins(100, 100, 100, 100);
      document.newPage();
      // step 3: add a paragraph to the document
      document.add(new Paragraph("Hello World"));
      document.newPage();
      document.add(new Paragraph("Hello World 2"));
      // step 4: we close the document
      document.close();