Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;

import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.util.Enumeration;

public class Main {
    public static NetworkInterface getActiveNetworkInterface() {

        Enumeration<NetworkInterface> interfaces = null;
        try {
            interfaces = NetworkInterface.getNetworkInterfaces();
        } catch (SocketException e) {
            return null;
        }

        while (interfaces.hasMoreElements()) {
            NetworkInterface iface = interfaces.nextElement();
            Enumeration<InetAddress> inetAddresses = iface.getInetAddresses();

            /* Check if we have a non-local address. If so, this is the active
             * interface.
             *
             * This isn't a perfect heuristic: I have devices which this will
             * still detect the wrong interface on, but it will handle the
             * common cases of wifi-only and Ethernet-only.
             */
            while (inetAddresses.hasMoreElements()) {
                InetAddress addr = inetAddresses.nextElement();

                if (!(addr.isLoopbackAddress() || addr.isLinkLocalAddress())) {
                    return iface;
                }
            }
        }

        return null;
    }
}