Java Program to Get System IP Address in Windows and Linux Machine

IP Address: An Internet Protocol address is a numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication. 

Packages used:

1. io (input-output): This package provides for system input and output through data streams, serialization, and the file system.
2. net (network): This package provides the classes for implementing networking applications.
3. util (utility): It contains the collection framework, legacy collection classes, event model, date and time facilities, internationalization, and miscellaneous utility classes

Methods Used:

1. getInetAddresses()

Syntax:

public Enumeration getInetAddresses()

Return Type: It returns an Enumeration of InetAddress.

2. getInterfaceAddresses()

Syntax:

public List getInterfaceAddresses()

Return Type: It returns a list of java.net.InterfaceAddress instances.

Below is the implementation of the problem statement:

Java

// Java Program to Get System IP Address
// in Windows and Linux Machine
import static java.lang.System.out;

import java.io.*;
import java.net.*;
import java.util.*;

public class gfg {
    public static void main(String args[]) // main method
        throws SocketException
    {
        // fetching network interface
        Enumeration<NetworkInterface> nets
            = NetworkInterface.getNetworkInterfaces();

        for (NetworkInterface netint :
             Collections.list(nets))
            displayInterfaceInformation(netint);
    }

    // Display Internet Information method
    static void
    displayInterfaceInformation(NetworkInterface netint)
        throws SocketException
    {
        out.printf("Display name: %s\n",
                   netint.getDisplayName());
        out.printf("Name: %s\n", netint.getName());
        Enumeration<InetAddress> inetAddresses
            = netint.getInetAddresses();
        // Output System IP
        for (InetAddress inetAddress :
             Collections.list(inetAddresses)) {
            out.printf("System IP: %s\n", inetAddress);
        }
        out.printf("\n");
    }
}

Output

Display name: eth0
Name: eth0

Display name: lo
Name: lo
System IP: /127.0.0.1

Output in Windows:

Output in Linux: