public static String getDefaultNetworkInterface()

in common/src/main/java/org/apache/omid/NetworkUtils.java [41:76]
31 lines of code
10 McCabe index (conditional complexity)

    public static String getDefaultNetworkInterface() {

        try (DatagramSocket s=new DatagramSocket()) {
            s.connect(InetAddress.getByAddress(new byte[]{1,1,1,1}), 53);
            return NetworkInterface.getByInetAddress(s.getLocalAddress()).getName();
        } catch (Exception e) {
            //fall through
        }

        //Fall back to old logic
        try {
            Enumeration<NetworkInterface> networkInterfaces = NetworkInterface.getNetworkInterfaces();
            String fallBackName = null;
            while (networkInterfaces.hasMoreElements()) {
                NetworkInterface nextElement = networkInterfaces.nextElement();
                String name = nextElement.getDisplayName();
                LOG.info("Iterating over network interfaces, found '{}'", name);
                boolean hasInet = Collections.list(nextElement.getInetAddresses()).size() > 0; // Checking that inet exists, to avoid taking iBridge
                if (hasInet && fallBackName == null) {
                    fallBackName = name;
                }
                if ((name.startsWith(MAC_TSO_NET_IFACE_PREFIX) && hasInet ) ||
                        name.startsWith(LINUX_TSO_NET_IFACE_PREFIX)) {
                  return name;
                }
            }
            if (fallBackName != null) {
                return fallBackName;
            }
        } catch (SocketException ignored) {
            throw new RuntimeException("Failed to find any network interfaces", ignored);
        }

        throw new IllegalArgumentException(String.format("No network '%s*'/'%s*' interfaces found",
                                                         MAC_TSO_NET_IFACE_PREFIX, LINUX_TSO_NET_IFACE_PREFIX));
    }