System.Net.Cache.HttpRequestCacheValidator.FinallyUpdateCacheEntry C# (CSharp) Method

        private void FinallyUpdateCacheEntry() {
            // Transfer the context status line back to the metadata

            CacheEntry.EntryMetadata  = null;
            CacheEntry.SystemMetadata = null;

            if (CacheHeaders == null) {
                //must be an entry update without updating the headers
                return;
            }

            CacheEntry.EntryMetadata  = new StringCollection();
            CacheEntry.SystemMetadata = new StringCollection();

            if (CacheHttpVersion == null) {
                if(Logging.On)Logging.PrintWarning(Logging.RequestCache, SR.GetString(SR.net_log_cache_invalid_http_version));
                CacheHttpVersion = new Version(1, 0);
            }
            // HTTP/1.1 200 OK
            System.Text.StringBuilder sb = new System.Text.StringBuilder(CacheStatusDescription.Length + 20);
            sb.Append("HTTP/");
            sb.Append(CacheHttpVersion.ToString(2));
            sb.Append(' ');
            sb.Append(((int)CacheStatusCode).ToString(NumberFormatInfo.InvariantInfo));
            sb.Append(' ');
            sb.Append(CacheStatusDescription);

            // Fetch the status line into cache metadata
            CacheEntry.EntryMetadata.Add(sb.ToString());

            UpdateStringCollection(CacheEntry.EntryMetadata,  CacheHeaders, false);

            if (SystemMeta != null)
            {
                UpdateStringCollection(CacheEntry.SystemMetadata, SystemMeta, true);
            }

            // Update other entry values
            if (ResponseExpires != DateTime.MinValue) {
                CacheEntry.ExpiresUtc = ResponseExpires;
            }

            if (ResponseLastModified != DateTime.MinValue)
            {
                CacheEntry.LastModifiedUtc = ResponseLastModified;
            }

            if (this.Policy.Level == HttpRequestCacheLevel.Default)
            {
                    CacheEntry.MaxStale = this.Policy.MaxStale;
            }

            CacheEntry.LastSynchronizedUtc = DateTime.UtcNow;
        }
        //