AppMetrics.DataReader.ReadSession C# (CSharp) Method

        public static Session ReadSession(string filePath, TimePeriod period)
        {
            try
            {
                var fileName = Path.GetFileNameWithoutExtension(filePath);
                var nameParts = fileName.Split('.');
                var sessionId = nameParts.Last();

                var timeText = nameParts.First().Replace('_', ':');
                var sessionCreationTime = Util.ParseDateTime(timeText);
                if (sessionCreationTime > period.EndTime)
                    return null;

                var lastUpdateTime = GetSessionLastWriteTime(filePath);
                if (lastUpdateTime < period.StartTime)
                    return null;

                return new Session
                    {
                        FileName = filePath,
                        Id = sessionId,
                        CreationTime = sessionCreationTime,
                        LastUpdateTime = lastUpdateTime,
                    };
            }
            catch (Exception exc)
            {
                var message = string.Format("Error in session file {0}", filePath);
                throw new ApplicationException(message, exc);
            }
        }