Org.BouncyCastle.Pkix.PkixNameConstraintValidator.IntersectIPRange C# (CSharp) Method

        private ISet IntersectIPRange(byte[] ipWithSubmask1, byte[] ipWithSubmask2)
    {
        if (ipWithSubmask1.Length != ipWithSubmask2.Length)
        {
            //Collections.EMPTY_SET;
            return new HashSet();
        }

        byte[][] temp = ExtractIPsAndSubnetMasks(ipWithSubmask1, ipWithSubmask2);
        byte[] ip1 = temp[0];
        byte[] subnetmask1 = temp[1];
        byte[] ip2 = temp[2];
        byte[] subnetmask2 = temp[3];

        byte[][] minMax = MinMaxIPs(ip1, subnetmask1, ip2, subnetmask2);
        byte[] min;
        byte[] max;
        max = Min(minMax[1], minMax[3]);
        min = Max(minMax[0], minMax[2]);

        // minimum IP address must be bigger than max
        if (CompareTo(min, max) == 1)
        {
            //return Collections.EMPTY_SET;
            return new HashSet();
        }
        // OR keeps all significant bits
        byte[] ip = Or(minMax[0], minMax[2]);
        byte[] subnetmask = Or(subnetmask1, subnetmask2);

            //return new HashSet( ICollectionsingleton(IpWithSubnetMask(ip, subnetmask));
        ISet hs = new HashSet();
        hs.Add(IpWithSubnetMask(ip, subnetmask));

            return hs;
    }