import java.net.Inet4Address;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;

public class NetworkUtil {
    
    public static String getMacAddress() {
        try {
            InetAddress ia = InetAddress.getLocalHost();
            byte[] mac = NetworkInterface.getByInetAddress(ia).getHardwareAddress();
            StringBuffer sb = new StringBuffer("");
            for(int i=0; i<mac.length; i++) {
                if(i!=0) {
                    sb.append("-");
                }
                int temp = mac[i]&0xff;
                String str = Integer.toHexString(temp);
                if(str.length()==1) {
                    sb.append("0"+str);
                }else {
                    sb.append(str);
                }
            }
            return sb.toString().toUpperCase();
        } catch (UnknownHostException | SocketException e) {
            e.printStackTrace();
            return null;
        }
    }
    
    public static List<String> getLocalIpAddress() throws SocketException {
        List<String> ipList = new ArrayList<>();
        try {
            Enumeration<NetworkInterface> allNetwork = NetworkInterface.getNetworkInterfaces();
            while (allNetwork.hasMoreElements()) {
                NetworkInterface netInterface = allNetwork.nextElement();
                if (netInterface.isLoopback() || netInterface.isVirtual()) {
                    continue;
                }
                Enumeration<InetAddress> inetAddress = netInterface.getInetAddresses();
                while(inetAddress.hasMoreElements()) {
                    InetAddress ip = inetAddress.nextElement() ;
                    if(ip != null && ip instanceof Inet4Address) {
                        ipList.add(ip.getHostAddress()) ;
                    }
                }               
            }
        } catch (SocketException ex) {
            throw ex ;
        }
        return ipList;
    }
    
}