Utils.java

package org.openiot.cupus.mobile.util;

import org.apache.http.conn.util.InetAddressUtils;

import java.net.InetAddress;
import java.net.NetworkInterface;
import java.util.Collections;
import java.util.List;

/**
 * Created by Kristijan on 30.01.14..
 */
public class Utils {
    /**
     * Get IP address from first non-localhost interface
     * @param useIPv4  true=return ipv4, false=return ipv6
     * @return  address or empty string
     */
    public static String getIPAddress(boolean useIPv4) {
        try {
            List<NetworkInterface> interfaces = Collections.list(NetworkInterface.getNetworkInterfaces());
            for (NetworkInterface intf : interfaces) {
                List<InetAddress> addrs = Collections.list(intf.getInetAddresses());
                for (InetAddress addr : addrs) {
                    if (!addr.isLoopbackAddress()) {
                        String sAddr = addr.getHostAddress().toUpperCase();
                        boolean isIPv4 = InetAddressUtils.isIPv4Address(sAddr);
                        if (useIPv4) {
                            if (isIPv4)
                                return sAddr;
                        } else {
                            if (!isIPv4) {
                                int delim = sAddr.indexOf('%'); // drop ip6 port suffix
                                return delim<0 ? sAddr : sAddr.substring(0, delim);
                            }
                        }
                    }
                }
            }
        } catch (Exception ex) { } // for now eat exceptions
        return "";
    }
}