// This partitioner that is simpler than the general case (don't use a list) is called in the case
// of initialPartitionSize == partitionMultiplier == 1
IEnumerator <KeyValuePair <long, T> > GetPartitionEnumeratorSimple(IEnumerator <T> src,
PartitionerState state,
bool last)
{
long index = -1;
var value = default(T);
try
{
do
{
lock (state.SyncLock)
{
if (!src.MoveNext())
{
break;
}
index = state.Index++;
value = src.Current;
}
yield return(new KeyValuePair <long, T> (index, value));
}while (true);
}
finally
{
if (last)
{
src.Dispose();
}
}
}
public override IList <IEnumerator <KeyValuePair <long, T> > > GetOrderablePartitions(int partitionCount)
{
if (partitionCount <= 0)
{
throw new ArgumentOutOfRangeException("partitionCount");
}
IEnumerator <KeyValuePair <long, T> >[] enumerators
= new IEnumerator <KeyValuePair <long, T> > [partitionCount];
PartitionerState state = new PartitionerState();
IEnumerator <T> src = source.GetEnumerator();
bool isSimple = initialPartitionSize == 1 && partitionMultiplier == 1;
for (int i = 0; i < enumerators.Length; i++)
{
enumerators[i] = isSimple ? GetPartitionEnumeratorSimple(src, state, i == enumerators.Length - 1) : GetPartitionEnumerator(src, state);
}
return(enumerators);
}
IEnumerator <KeyValuePair <long, T> > GetPartitionEnumerator(IEnumerator <T> src, PartitionerState state)
{
int count = initialPartitionSize;
List <T> list = new List <T> ();
while (true)
{
list.Clear();
long ind = -1;
lock (state.SyncLock)
{
ind = state.Index;
for (int i = 0; i < count; i++)
{
if (!src.MoveNext())
{
if (list.Count == 0)
{
yield break;
}
else
{
break;
}
}
list.Add(src.Current);
state.Index++;
}
}
for (int i = 0; i < list.Count; i++)
{
yield return(new KeyValuePair <long, T> (ind + i, list[i]));
}
count *= partitionMultiplier;
}
}