Thread: How to get your computer name and IP address?

This code will print your workstations name and IP address:

public class NetInfo {
     public static void main(String[] args) {
        new NetInfo().say();
        }
 
     public void say() {
       try {
       java.net.InetAddress i = java.net.InetAddress.getLocalHost();
       System.out.println(i);                  // name and IP address
       System.out.println(i.getHostName());    // name
       System.out.println(i.getHostAddress()); // IP address only
       }
       catch(Exception e){e.printStackTrace();}
     }
    }

Sample output:

homepc/10.210.65.8
homepc
10.210.65.8

This code will list the interfaces available on a workstation:

import java.net.*;
import java.util.*;
import java.io.*;
import java.nio.*;
 
public class IPAddress {
 public void  getInterfaces (){
      try {
         Enumeration e = NetworkInterface.getNetworkInterfaces();
 
         while(e.hasMoreElements()) {
            NetworkInterface ni = (NetworkInterface) e.nextElement();
            System.out.println("Net interface: "+ni.getName());
 
            Enumeration e2 = ni.getInetAddresses();
 
            while (e2.hasMoreElements()){
               InetAddress ip = (InetAddress) e2.nextElement();
               System.out.println("IP address: "+ ip.toString());
            }
         }
      }
      catch (Exception e) {
         e.printStackTrace();
      }
   }
 
   public static void main(String[] args) {
    IPAddress ip = new IPAddress();
    ip.getInterfaces();
   }
}

Sample output:

Net interface: lo
IP address: /127.0.0.1
Net interface: eth0
IP address: /10.210.62.4

Use the default command for running a java program via command-line. Note that you will need to pass both class files to the jvm. Alternatively, you can set the classpath.

java IPAddress CLASSPATH=%THE_PATH%
rem the path is the path(s) of the class files. Only one path is required if they're both in the same folder