Not displaying all ip addresses connected to the network

Question

import java.io.*;
import java.net.*;
import java.util.*;
import static java.lang.System.out;
public class ListNets
public static void main(String args[]) throws SocketException {
Enumeration<NetworkInterface> nets = NetworkInterface.getNetworkInterfaces();
for (NetworkInterface netint : Collections.list(nets))
displayInterfaceInformation(netint);
static void displayInterfaceInformation(NetworkInterface netint) throws SocketException {
Enumeration<InetAddress> inetAddresses = netint.getInetAddresses();
while(inetAddresses.hasMoreElements()==true)
System.out.println(inetAddresses.nextElement());
The output of this code gives only the ip of the computer im working on the network :192.168.1.101 and the local ip 127.0.0.1
although there are other computers connected to the netwrok .. i need to get all the ips connected including the ip of the router so if any 1 can please help me
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Answer 1

There is no general way to do what you want to do, which is sometimes called host discovery. Look at the design of port scanners such as nmap (insecure.org) to see how hard it can be. It is even harder in Java because you don't have raw sockets, so you can't send ICMP packets to see who responds. If you read carefully the discussion surrounding the options to nmap to do host discovery using UDP and TCP you may get some ideas that will work for your network.