Code Worked
Image i = Image.createImage(path);
Graphics g= i.getGraphics();
g.drawString("CopyWrite:Capital Eye", 20, 20);
String img_name=System.currentTimeMillis()+".png";
String realpath=FileSystemStorage.getInstance().getAppHomePath();
OutputStream out= FileSystemStorage.getInstance().openOutputStream( realpath+img_name);
ImageIO.getImageIO().save(i, out, ImageIO.FORMAT_PNG, 1f);