public IEnumerable <KeyValuePair <IData, IData> > Forward(IData from, bool hasFrom, IData to, bool hasTo)
{
if (hasFrom && hasTo && Locator.KeyComparer.Compare(from, to) > 0)
{
throw new ArgumentException("from > to");
}
Flush();
StorageEngine.FullKey nearFullKey;
bool hasNearFullKey;
WTree.FullKey lastVisitedFullKey = default(WTree.FullKey);
IOrderedSet <IData, IData> records;
records = (IOrderedSet <IData, IData>)StorageEngine.FindData(Locator, Locator, hasFrom ? from : null, Direction.Forward, out nearFullKey, out hasNearFullKey, ref lastVisitedFullKey);
if (records == null)
{
if (!hasNearFullKey || !nearFullKey.Locator.Equals(Locator))
{
yield break;
}
records = (IOrderedSet <IData, IData>)StorageEngine.FindData(Locator, nearFullKey.Locator, nearFullKey.Key, Direction.Forward, out nearFullKey, out hasNearFullKey, ref lastVisitedFullKey);
}
while (records != null)
{
Task task = null;
IOrderedSet <IData, IData> recs = null;
if (hasNearFullKey && nearFullKey.Locator.Equals(Locator))
{
if (hasTo && records.Count > 0 && Locator.KeyComparer.Compare(records.First.Key, to) > 0)
{
break;
}
task = Task.Factory.StartNew(() =>
{
recs = (IOrderedSet <IData, IData>)StorageEngine.FindData(Locator, nearFullKey.Locator, nearFullKey.Key, Direction.Forward, out nearFullKey, out hasNearFullKey, ref lastVisitedFullKey);
});
}
foreach (var record in records.Forward(from, hasFrom, to, hasTo))
{
yield return(record);
}
if (task != null)
{
task.Wait();
}
records = recs;
}
}
public bool TryGet(IData key, out IData record)
{
Flush();
StorageEngine.FullKey nearFullKey;
bool haveNearLocator;
WTree.FullKey lastVisitedFullKey = default(WTree.FullKey);
var records = (IOrderedSet <IData, IData>)StorageEngine.FindData(Locator, Locator, key, Direction.Forward, out nearFullKey, out haveNearLocator, ref lastVisitedFullKey);
if (records == null)
{
record = default(IData);
return(false);
}
return(records.TryGetValue(key, out record));
}
public bool TryGet(IData key, out IData record)
{
lock (SyncRoot)
{
Flush();
WTree.FullKey nearFullKey;
bool hasNearLocator;
WTree.FullKey lastVisitedFullKey = default(WTree.FullKey);
var records = Tree.FindData(Locator, Locator, key, Direction.Forward, out nearFullKey, out hasNearLocator, ref lastVisitedFullKey);
if (records == null)
{
record = default(IData);
return(false);
}
lock (records)
{
return(records.TryGetValue(key, out record));
}
}
}
public IEnumerable <KeyValuePair <IData, IData> > Backward(IData to, bool hasTo, IData from, bool hasFrom)
{
lock (SyncRoot)
{
var keyComparer = Locator.KeyComparer;
if (hasFrom && hasTo && keyComparer.Compare(from, to) > 0)
{
throw new ArgumentException("from > to");
}
Flush();
WTree.FullKey nearFullKey;
bool hasNearFullKey;
IOrderedSet <IData, IData> records;
WTree.FullKey lastVisitedFullKey = new WTree.FullKey(Locator, to);
records = Tree.FindData(Locator, Locator, hasTo ? to : null, Direction.Backward, out nearFullKey, out hasNearFullKey, ref lastVisitedFullKey);
if (records == null)
{
yield break;
}
while (records != null)
{
Task task = null;
IOrderedSet <IData, IData> recs = null;
//if (records.Count > 0)
// lastVisitedFullKey = new WTree.FullKey(Locator, records.First.Key);
if (hasNearFullKey)
{
lock (records)
{
if (hasFrom && records.Count > 0 && keyComparer.Compare(records.Last.Key, from) < 0)
{
break;
}
}
task = Task.Factory.StartNew(() =>
{
recs = Tree.FindData(Locator, nearFullKey.Locator, nearFullKey.Key, Direction.Backward, out nearFullKey, out hasNearFullKey, ref lastVisitedFullKey);
});
}
lock (records)
{
foreach (var record in records.Backward(to, hasTo, from, hasFrom))
{
yield return(record);
}
}
if (task != null)
{
task.Wait();
}
if (recs == null)
{
break;
}
lock (records)
{
lock (recs)
{
if (recs.Count > 0 && records.Count > 0)
{
if (keyComparer.Compare(recs.First.Key, records.First.Key) >= 0)
{
break;
}
}
}
}
records = recs;
}
}
}
