public override bool MoveNext()
{
if (_partitionRecordSets.Count == 0)
{
return(false);
}
IRecordSetEnumerator rse = _partitionRecordSets[0];
_current = _partitionRecordSets[0].Current;
foreach (IRecordSetEnumerator rs in _partitionRecordSets)
{
if (_current.CompareOrder(rs.Current, _orderByArguments) > 0)
{
_current = rs.Current;
rse = rs;
}
}
if (!rse.MoveNext())
{
_partitionRecordSets.Remove(rse);
RemoveFromValidReaders(rse);
}
if (_current == null)
{
return(false);
}
return(true);
}
public PartitionRSEnumerator(IRecordSetEnumerator recordSetEnumerator, string readerId, string nodeIP, int nextIdex, IRecordSetLoader cacheImpl)
{
_recordSetEnumerator = recordSetEnumerator;
_readerId = readerId;
_nodeIP = nodeIP;
_nextIndex = nextIdex;
_cacheImpl = cacheImpl;
}
internal CacheDataReader(IRecordSetEnumerator recordSetEnumerator)
{
_recordSetEnumerator = recordSetEnumerator;
_columns = _recordSetEnumerator != null ? _recordSetEnumerator.ColumnCollection : null;
if (_columns != null)
{
_hiddenColumnCount = _columns.HiddenColumnCount;
}
}
public PartitionRSEnumerator(IRecordSetEnumerator recordSetEnumerator, string readerId, string nodeIP, int nextIdex, IRecordSetLoader cacheImpl)
{
_recordSetEnumerator = recordSetEnumerator;
_readerId = readerId;
_nextIndex = nextIdex;
_cacheImpl = cacheImpl;
uniqueId = Guid.NewGuid().ToString();
ParseAddress(nodeIP);
}
private void SetCurrentEnumerator() //for each move next,call pick one of partition record set.
{
if (_partitionRecordSets.Count == 0)
{
return;
}
bool hasNext = false;
do
{
try
{
if (_partitionRecordSets.Count <= _counter)
{
throw new InvalidReaderException("Data reader has lost its state");
}
_currentRecordSet = _partitionRecordSets[_counter];
hasNext = _currentRecordSet.MoveNext();
}
catch (InvalidReaderException e)
{
this.Dispose();
throw;
}
catch (Exception e)
{
throw;
}
if (hasNext)
{
_current = _currentRecordSet.Current;
}
else
{
_partitionRecordSets.Remove(_currentRecordSet);
RemoveFromValidReaders(_currentRecordSet);
}
_counter++;
if (_counter >= _partitionRecordSets.Count)
{
_counter = 0;
}
} while (!hasNext && _partitionRecordSets.Count > 0);
_next = hasNext;
}
public void RemoveFromValidReaders(IRecordSetEnumerator pe)
{
IPartitionInfo info = pe as IPartitionInfo;
if (info != null)
{
var readers = default(Dictionary <IRecordSetEnumerator, Object>);
lock (_validReaders)
{
_validReaders.TryGetValue(info.Server, out readers);
if (readers != null)
{
readers.Remove(pe);
}
}
}
}
public bool GetNextRecordSetChunk()
{
ReaderResultSet readerChunk = null;
if (_cacheImpl != null)
{
if (!isValid)
{
throw new InvalidReaderException("Reader state has been lost.");
}
readerChunk = _cacheImpl.GetRecordSet(_readerId, _nodeIP, _nextIndex);
}
if (readerChunk != null && readerChunk.RecordSet != null && readerChunk.RecordSet.RowCount > 0)
{
_recordSetEnumerator = new RecordSetEnumerator(readerChunk.RecordSet);
_nextIndex = readerChunk.NextIndex;
return(_recordSetEnumerator.MoveNext());
}
return(false);
}
