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Dear all
I write this code to get the remote user but it returns null

 FacesContext ctx = FacesContext.getCurrentInstance();
                          ExternalContext ectx = ctx.getExternalContext();
                          HttpServletRequest request = (HttpServletRequest)ectx.getRequest();
                          System.out.println(request.getHeader("REMOTE_USER"));                         

the result is null.
can any one help me how to get the remote user name.

Thanks