Question

I have a servlet where I want when a user press one button, it will generate a dynamic pdf (according to user given data) and download it to user’s c:/ location. Can anybody help me how to do that ?

Answer 1

What exactly is unclear to you? How to write an html form? How to get parameters from HttpServletRequest? Or how to generate pdf and download to user?

<form action="yourServlet">
 <input type="text" name="sometxt"/>
 <input type="secret" name="passwd"/>
 <input type="submit"/>
</form>

Then, you can retrieve it in your getXXX method like

final String text  = request.getParameter("sometxt");
final String rawPassword = request.getParameter("secret");

If you need to render a pdf, you should look on Apache PdfBox.

And finally, if you in trouble with downloading file to user:

response.setContentType("application/pdf");
InputStream in = ... // depends where you store your file 
ServletOutputStream out = response.getOutputStream();
byte[] buffer = new byte[4096];
while(in.read(buffer, 0, 4096) != -1)
   out.write(buffer, 0, 4096);
in.close();
out.flush();
out.close();

And don’t forget about handilng IOException, which i missed in simpicity purposes.