System.Web.Caching.Cache.Add C# (CSharp) Method

		public object Add (string key, object value, CacheDependency dependencies, DateTime absoluteExpiration, TimeSpan slidingExpiration, CacheItemPriority priority, CacheItemRemovedCallback onRemoveCallback)
		{
			if (key == null)
				throw new ArgumentNullException ("key");
			
			try {
				cacheLock.EnterWriteLock ();
				CacheItem it = cache [key];

				if (it != null)
					return it.Value;
				Insert (key, value, dependencies, absoluteExpiration, slidingExpiration, priority, onRemoveCallback, null, false);
			} finally {
				// See comment at the top of the file, above cacheLock declaration
				cacheLock.ExitWriteLock ();
			}
				
			return null;
		}
		

        public static AggregationCategorizationService GetService(Cache cache, String userId)
        {

            try
            {
                if (cache["AggCatService_" + userId] == null)
                {
                    string certificateFile = System.Configuration.ConfigurationManager.AppSettings["PrivateKeyPath"];
                    string password = System.Configuration.ConfigurationManager.AppSettings["PrivateKeyPassword"];
                    X509Certificate2 certificate = new X509Certificate2(certificateFile, password);

                    string consumerKey = System.Configuration.ConfigurationManager.AppSettings["ConsumerKey"];
                    string consumerSecret = System.Configuration.ConfigurationManager.AppSettings["ConsumerSecret"];
                    string issuerId = System.Configuration.ConfigurationManager.AppSettings["SAMLIdentityProviderID"];

                    SamlRequestValidator samlValidator = new SamlRequestValidator(certificate, consumerKey, consumerSecret, issuerId, userId);

                    ServiceContext ctx = new ServiceContext(samlValidator);
                    cache.Add("AggCatService_" + userId, new AggregationCategorizationService(ctx), null, DateTime.Now.AddMinutes(50),
                              Cache.NoSlidingExpiration, CacheItemPriority.High, null);
                }
                return (AggregationCategorizationService)cache["AggCatService_" + userId];
            }
            catch (Exception ex)
            {
                throw new Exception("Unable to create AggCatService: " + ex.Message);
            }
        }