Candor.Data.SequenceIdGenerator.GetSequenceIdStore C# (CSharp) Метод

        private SequenceIdStore GetSequenceIdStore(String tableName)
        {
            var sequence = _sequences[tableName];
            if (sequence == null || sequence.Schema == null)
            {
                lock (_sequencesLock)
                {
                    if (sequence == null || sequence.Schema == null)
                    {
                        sequence = _store.GetSequenceIdStore(tableName);
                        if (sequence != null)
                            _sequences[tableName] = sequence;
                    }
                }
            }
            if (sequence == null)
                throw new InvalidOperationException(String.Format("Sequence '{0}' is not defined.", tableName));
            return sequence;
        }