FAQ: How do you redirect a request to a different URL?

How do you redirect a request to a different URL?

There are two ways to redirect a request to a different URL:

1) use HttpServletResponse's sendRedirect() function:

public void sendRedirect(String location) throws IOException

Notes:

do not send a response body before calling sendRedirect().
any code in the servlet after the sendRedirect() will not be executed. the client will be immediately redirected to the new URL.

2) set the HTTP response header's Refresh field:

res.setHeader("Refresh", delay + "; URL=" + location)

where delay is the number of seconds to wait before the browser requests the new location

Notes:

the header must be set before sending your response body
this method is useful if you want to display a message before redirecting the client to a different URL

For example,

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class RedirectURL extends HttpServlet {

public void doGet(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException
{
// set the content type
res.setContentType("text/html");
PrintWriter out = res.getWriter();

// instruct the browser to wait 5 seconds before redirecting to a new URL
res.setHeader("Refresh", "5; URL=http://www.keysolutions.com");

// output a message that notifies the user that the browser is
// going to be redirected to a new page
out.println("<HTML>");
out.println("<BODY>");
out.println("The page you requested could not be found.<BR>");
out.println("Your browser will automatically take you<BR>");
out.println("to our home page in 5 seconds.<BR>");
out.println("</BODY>");
out.println("</HTML>");
}
}

Last updated 01/03/2000 10:40:48 PM