proxy_set_header X-Real-IP          $remote_addr;proxy_set_header X-Forwarded-For    $proxy_add_x_forwarded_for;proxy_set_header Host $host:$server_port; proxy_set_header X-Forwarded-Proto "https";proxy_set_header X-Forwarded-Host $host;proxy_set_header X-Forwarded-Server $host;

public class NetworkUtil {    private static final String[] HEADERS_TO_TRY = {         "X-Forwarded-For",        "Proxy-Client-IP",         "WL-Proxy-Client-IP",        "HTTP_X_FORWARDED_FOR",        "HTTP_X_FORWARDED",        "HTTP_X_CLUSTER_CLIENT_IP",        "HTTP_CLIENT_IP",        "HTTP_FORWARDED_FOR",        "HTTP_FORWARDED",        "HTTP_VIA",        "REMOTE_ADDR"     };
    public static String getRemoteHost(HttpServletRequest request) {        for (String header : HEADERS_TO_TRY) {            String ip = request.getHeader(header);            if (ip != null && ip.length() != 0 && !"unknown".equalsIgnoreCase(ip)) {                return ip;            }        }        return request.getRemoteAddr();    }}