public void AggregateState(Guid channelId)
        {
            List <CommandStateSource> stateList  = _GetChannelStateList(channelId);
            CommandStateAggregator    aggregator = _GetChannelAggregator(channelId);

            aggregator.Aggregate(stateList);
        }
        private CommandStateAggregator _GetChannelAggregator(Guid channelId)
        {
            CommandStateAggregator aggregator;

            if (!_channelStates.TryGetValue(channelId, out aggregator))
            {
                aggregator = new CommandStateAggregator();
                _channelStates[channelId] = aggregator;
            }

            return(aggregator);
        }