response.sendError(403), but return is 404

the code like this:

void doFilter(request, response, chain){
  try{
    //something code process
    chain.doFilter(request,response);
  }
  catch(Exception e){
    response.sendError(403,"Forbidden");
  }

}

directly visit the web project, not pass nginx and something like that. but the status return is always 404, is here someone who can help me? thanks a lot.