How do I get MAC address of a host ?

Use getHardwareAddress() method from java.net.NetworkInterface class.

Code

try {

  InetAddress address = InetAddress.getLocalHost();

  //InetAddress address = InetAddress.getByName("www.google.co.in");

   

  System.out.println("Current IP address: " + 

                       address.getHostAddress());

  NetworkInterface network = 

       NetworkInterface.getByInetAddress(address);

  byte[] mac = network.getHardwareAddress();

  System.out.print("Current MAC address : ");

  StringBuilder sb = new StringBuilder();

  for (int i = 0; i < mac.length; i++) {

      sb.append(

         String.format("%02X%s", mac[i], (i<mac.length-1)?"-":"")

      );

  }

  System.out.println(sb.toString());

} catch (UnknownHostException e) {

  ...

} catch (SocketException e){

  ...

}