Multiple response streams ? HTML and binary ?

Question

Hello,
Is it possible for a Servlet to create two responses or two output streams, with one as HTML and the other as binary?
The code below only seems to send the first (HTML) section and seems to ignore the second (binary) section ?
Thanks alot !!!
James
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
public class MinimalBinaryStream extends HttpServlet
  public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
    doGet(request, response);
  public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    /*----------Below: Send HTML Response----------*/
    response.setContentType("text/html");
    ServletOutputStream out = response.getOutputStream();
    out.print("<h3>Text message to say binary file is on its way</h3>");
    out.flush();
    out.close();
    /*----------Below: Send Binary Response----------*/
    response.reset();
    response.setContentType("application/octet-stream");
    response.setContentLength(3);
    out = response.getOutputStream();
    out.write(0x31);
    out.write(0x32);
    out.write(0x33);
    out.flush();
    out.close();
}

Answer 1

The servlet validates the serial number. If the
serial number submitted is invalid, then the servlet
simply sends an HTML message to the client saying
"Invalid serial number, please try again, etc,
etc".
If the serial number is valid, then the server
encrypts it into a ZIP file and sends the ZIP file to
the client. (This part is working perfectly by the
way.)It sounds like you're not really mixing the two types of data in a single response... You're doing one or the other depending upon the value of some data the client has sent to the server
I wouldn't use the sendRedirect method off of the response. That causes a new get request to be issued from the client which is not necessary. I'd use the RequestDispatcher, preserving the initial request and forwarding both the request and response to another resource on the server. The client is unaware of any of it.
if ( serial number valid ) {
     // encrypt to ZIP
     // send zip to client on response...
} else {
     ResquestDispatcher dispatcher = request.getRequestDispatcher( "redirect.html" );
     dispatcher.forward( request, response );
}http://java.sun.com/j2ee/1.4/docs/api/javax/servlet/RequestDispatcher.html
What would be really nice, is if the servlet could
also send an HTML message saying "Thanks for your
serial number, here is your licence.ZIP, etc,
etc".For this, maybe you could create a jsp page with a link that pointed to the ZIP file on the server. You would define the name dynamically, and attach the name to the request via setAttribute. Then use that same value in the href value on the jsp page. via request.getAttribute The jsp page would contain the message in html and the client would obtain the zip from the link. And use the RequestDispatcher to forward to the jsp page from the servlet. Place the jsp inside /WEB-INF so that by itself it is not accessble to the client. Only the server code can get to it.