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    <p>On my laptop (running Windows 7, with Virtual Box and it's network interface installed) the following code prints out the name of my wireless interface along with my local address. It uses a brute force approach at the end of the day, but will only try and actually connect to addresses that are considered to be the best candidates.</p> <pre><code>// iterate over the network interfaces known to java Enumeration&lt;NetworkInterface&gt; interfaces = NetworkInterface.getNetworkInterfaces(); OUTER : for (NetworkInterface interface_ : Collections.list(interfaces)) { // we shouldn't care about loopback addresses if (interface_.isLoopback()) continue; // if you don't expect the interface to be up you can skip this // though it would question the usability of the rest of the code if (!interface_.isUp()) continue; // iterate over the addresses associated with the interface Enumeration&lt;InetAddress&gt; addresses = interface_.getInetAddresses(); for (InetAddress address : Collections.list(addresses)) { // look only for ipv4 addresses if (address instanceof Inet6Address) continue; // use a timeout big enough for your needs if (!address.isReachable(3000)) continue; // java 7's try-with-resources statement, so that // we close the socket immediately after use try (SocketChannel socket = SocketChannel.open()) { // again, use a big enough timeout socket.socket().setSoTimeout(3000); // bind the socket to your local interface socket.bind(new InetSocketAddress(address, 8080)); // try to connect to *somewhere* socket.connect(new InetSocketAddress("google.com", 80)); } catch (IOException ex) { ex.printStackTrace(); continue; } System.out.format("ni: %s, ia: %s\n", interface_, address); // stops at the first *working* solution break OUTER; } } </code></pre> <p><sub>(I've updated my answer with <code>isReachable(...)</code> based on <a href="https://stackoverflow.com/users/383688/mockertim">Mocker Tim's</a> answer.)</sub></p> <p>One thing to watch out for. <code>socket.bind(...)</code> would bark at me that the address and port is already in use if I tried to run my code too fast in succession like the connection isn't cleaned up fast enough. <code>8080</code> should be a random port maybe.</p>
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    1. POHow to Determine Internet Network Interface in Java
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    1. POHow to Determine Internet Network Interface in Java
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    1. COThis returns the interface I want and the two VMWare interfaces on my computer. The interface I want is first, but I don't really want to rely on that being true all the time.
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      1. USCavyn VonDeylen
    2. CO@CavynVonDeylen If you can describe your use-case we could propose *some sort* of solution. However, there'll be no *clean* way to do this. My first guess is that you should filter the addresses by their IP: throw away addresses *not* starting with `192.168.1`. Yeah, it's *barbaric*.
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    3. COThanks! This code works for me. I'm surprised Java doesn't offer some easy way to do this, as I'd think this would be a fairly common issue. Maybe in Java 8.
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