Re: Regarding subnet mask of a virtual machine.

Here is script. The netmask of the first address of the  interface:

InetAddress localHost = Inet4Address.getLocalHost();

NetworkInterface networkInterface = NetworkInterface.getByInetAddress(localHost);

for (InterfaceAddress address : networkInterface.getInterfaceAddresses()) {
    System.out.println(address.getNetworkPrefixLength());
}

Regards,
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