private static void UpdateEndpoint(String regionId, String product, String domain, Endpoint endpoint)
        {
            ISet<String> regionIds = endpoint.RegionIds;
            regionIds.Add(regionId);

            List<ProductDomain> productDomains = endpoint.ProductDomains;
            ProductDomain productDomain = FindProductDomain(productDomains, product);
            if (null == productDomain)
            {
                productDomains.Add(new ProductDomain(product, domain));
            }
            else
            {
                productDomain.DomianName = domain;
            }
        }
        private static void AddEndpoint_(String endpointName, String regionId, String product, String domain)
        {
            ISet<String> regions = new HashSet<String>();
            regions.Add(regionId);

            List<ProductDomain> productDomains = new List<ProductDomain>();
            productDomains.Add(new ProductDomain(product, domain));
            Endpoint endpoint = new Endpoint(endpointName, regions, productDomains);
            endpoints.Add(endpoint);
        }