Hello, everybody:
I run this
servlet code, I expect it will output "head3", to my suprise, it prints null, can anybody explain it? Thanks a lot.
public doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
PrintWriter out = response.getWriter();
response.addHeader("a", "head1");
response.addHeader("a", "head2");
response.setHeader("a", "head3");
String s = request.getHeader("a");
out.println(s);
}
later, I tried this code, the output is also null.
...
{
...
response.addHeader("a", "head1");
String s = request.getHeader("a");
out.println(s);
}
Please explain it. Thanks.