import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Enumeration;

public class IpAddressUtil {
    private static final String[] IP_HEADER_CANDIDATES = {
            "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 getClientIpAddress(HttpServletRequest request) {
        String ip = null;
        for (String header : IP_HEADER_CANDIDATES) {
            ip = request.getHeader(header);
            if (ip != null && ip.length() != 0 && !"unknown".equalsIgnoreCase(ip)) {
                return ip;
            } else {
                String remoteAddr=request.getRemoteAddr();
                if (remoteAddr.equals("127.0.0.1") || remoteAddr.equals("0:0:0:0:0:0:0:1")) {
                    try {
                        ip = InetAddress.getLocalHost().getHostAddress();
                    } catch (UnknownHostException ex) {
                        ex.printStackTrace();
                    }
                    break;
                }
            }
        }
        return ip;
    }

    public static String getLocalAddress() {
        try {
            for (Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces(); interfaces.hasMoreElements(); ) {
                NetworkInterface networkInterface = interfaces.nextElement();
                if (networkInterface.isLoopback() || networkInterface.isVirtual() || !networkInterface.isUp()) {
                    continue;
                }
                Enumeration<InetAddress> addresses = networkInterface.getInetAddresses();
                if (addresses.hasMoreElements()) {
                    return addresses.nextElement().getHostAddress();
                }
            }
        } catch (SocketException e) {
            e.printStackTrace();
        }
        return null;
    }
}