import java.io.FileOutputStream;
import com.lowagie.text.pdf.BaseFont;
import com.lowagie.text.pdf.PdfContentByte;
import com.lowagie.text.pdf.PdfReader;
import com.lowagie.text.pdf.PdfStamper;
public class MainClass {
public static void main(String[] args) throws Exception {
PdfReader reader = new PdfReader("HelloWorldRead.pdf");
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream("HelloWorldStamper.pdf"));
BaseFont bf = BaseFont.createFont(BaseFont.HELVETICA, BaseFont.WINANSI, BaseFont.NOT_EMBEDDED);
PdfContentByte over;
int total = reader.getNumberOfPages() + 1;
for (int i = 1; i < total; i++) {
over = stamper.getOverContent(i);
over.beginText();
over.setFontAndSize(bf, 18);
over.setTextMatrix(30, 30);
over.showText("page " + i);
over.endText();
over.setRGBColorStroke(0xFF, 0x00, 0x00);
over.setLineWidth(5f);
over.ellipse(250, 450, 350, 550);
over.stroke();
}
stamper.close();
}
}