Server-side scripting languages allow developers to set the non-standard HTTP header "Refresh" with a time-out (in seconds) and a URI to which the browser is redirected after the specified time-out. If the time interval is too short, people who are blind will not have enough time to make their screen readers read the page before the page refreshes unexpectedly and causes the screen reader to begin reading at the top. Sighted users may also be disoriented by the unexpected refresh.
The HTTP header that is set is Refresh: {time in seconds}; url={URI of new location}. It is also possible to omit the URI and obtain a periodically refreshing page, which causes the same problem. The HTTP header that is set is Refresh: {time in seconds}.
The following example is a failure because a timed server-side redirect is implemented in Java Servlets or JavaServer Pages (JSP).
public void doGet (HttpServletRequest request, HttpServletResponse response)
throws IOException, ServletException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
response.setHeader("Refresh", "10; URL=TargetPage.html");
out.println("<!DOCTYPE html>");
out.println("<html><head><title>Redirect</title></head><body>");
out.println("<p>This page will redirect you in 10 seconds.</p>");
out.println("</body></html>");
}