Use this to determine the names of your network interfaces and IPs. Of course, it can be used only for machines that have more than one network interface.

import java.io.*;import java.net.*;import java.util.*;public class NetInterfaces{   public static void main(String argv[]) throws Exception {   Enumeration enumInterfaces=NetworkInterface.getNetworkInterfaces();while(enumInterfaces.hasMoreElements()) { NetworkInterface net=(NetworkInterface)enumInterfaces.nextElement(); System.out.println("NetworkInterface name: "+net.getDisplayName());   Enumeration enumIP=net.getInetAddresses();   while(enumIP.hasMoreElements())          {          InetAddress ip=(InetAddress)enumIP.nextElement();          System.out.println("IP address:"+ip);          }       }   } }