Java - List all physical address

import java.io.PrintStream;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.util.Collections;
import java.util.Enumeration;

public class ListMacAddress {
    public static void main(String[] args) throws SocketException {
        final PrintStream out = System.out;
        final Enumeration<NetworkInterface> networkInterfaces = NetworkInterface.getNetworkInterfaces();
        displayInformationAbout(networkInterfaces, out);
    }
    private static void displayInformationAbout(final Enumeration<NetworkInterface> networkInterfaces, final PrintStream out) throws SocketException {
        for (NetworkInterface networkInterface : Collections.list(networkInterfaces)) {
            out.printf("%s (%s) - %s [%s]%n",
                    networkInterface.getName(),
                    networkInterface.getDisplayName(),
                    ip(networkInterface),
                    hardware(networkInterface));
            displayInformationAbout(networkInterface.getSubInterfaces(), out);
        }
    }
    private static String ip(final NetworkInterface networkInterface) {
        final StringBuilder builder = new StringBuilder();
        final Enumeration<InetAddress> inetAddresses = networkInterface.getInetAddresses();
        while (inetAddresses.hasMoreElements()) {
            final InetAddress inetAddress = inetAddresses.nextElement();
            builder.append(inetAddress.getHostAddress());
            if(inetAddresses.hasMoreElements()){
                builder.append(":");
            }
        }
        return builder.toString();
    }
    private static String hardware(final NetworkInterface networkInterface) throws SocketException {
        final byte[] hardwareAddress = networkInterface.getHardwareAddress();
        return hardwareAddress == null ? "" : readable(hardwareAddress);
    }
    private static String readable(byte[] hardwareAddress) {
        if(hardwareAddress == null) return "";
        final StringBuilder builder = new StringBuilder('[');
        for (int i = 0; i < hardwareAddress.length; i++) {
            byte b = hardwareAddress[i];
            builder.append(String.format("%02X", b));
            if(i < hardwareAddress.length - 1){
                builder.append(':');
            }
        }
        return builder.append(']').toString();
    }
}