I got a html form in /form.jsp which calls a servlet, /validate, to validate form information. if validation doesn't pass, it gets redirected back to form.jsp with error message. to differentiate different types of messages, i pass params to forms.jsp like form.jsp?error=1. However, I don't want to allow people seeing the error message unless it comes from the servlet /validate. I tried using getHeader("referer"), but it seems to get the form.jsp header rather than the /validate servlet. any way around this? Thanks.