Java 獲取 mac 地址

從es代碼裏面看到的, 注意, 一個機器可能有多個mac地址, 代碼中取出第一個有效的

private static byte[] getMacAddress() throws SocketException {
        Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces();
        if (en != null) {
            while (en.hasMoreElements()) {
                NetworkInterface nint = en.nextElement();
                if (!nint.isLoopback()) {
                    // Pick the first valid non loopback address we find
                    byte[] address = nint.getHardwareAddress();
                    if (isValidAddress(address)) {
                        return address;
                    }
                }
            }
        }
        // Could not find a mac address
        return null;
    }

    private static boolean isValidAddress(byte[] address) {
        if (address == null || address.length != 6) {
            return false;
        }
        for (byte b : address) {
            if (b != 0x00) {
                return true; // If any of the bytes are non zero assume a good
                             // address
            }
        }
        return false;
    }