public List <byte[]> GetLatestValues(ISnapshot head, long limit)
{
List <byte[]> result = new List <byte[]>();
lock (lock_db)
{
if (limit <= 0)
{
return(result);
}
long temp = limit;
ISnapshot snapshot = this.head;
for (; temp > 0 && snapshot.GetPrevious() != null; snapshot = snapshot.GetPrevious())
{
if (!((Snapshot)(snapshot)).DB.IsEmpty)
{
--temp;
result.AddRange(((Snapshot)(snapshot)).DB.Select(data => data.Value.Data).ToList());
}
}
if (snapshot.GetPrevious() == null && temp != 0)
{
foreach (var value in (((Common.LevelDB)((SnapshotRoot)snapshot).DB)).DB.GetLatestValues(temp))
{
result.Add(value);
}
}
}
return(result);
}
public List <byte[]> GetValuesNext(ISnapshot snapshot, byte[] key, long limit)
{
List <byte[]> result = new List <byte[]>();
if (limit <= 0)
{
return(result);
}
Dictionary <WrappedByteArray, WrappedByteArray> collection = new Dictionary <WrappedByteArray, WrappedByteArray>(new WrapperdByteArrayEqualComparer());
if (snapshot.GetPrevious() != null)
{
((Snapshot)(snapshot)).Collect(collection);
}
Dictionary <byte[], byte[]> db_dictonary =
new Dictionary <byte[], byte[]>((((Common.LevelDB)((SnapshotRoot)snapshot.GetRoot()).DB).DB.GetNext(key, limit)));
foreach (KeyValuePair <WrappedByteArray, WrappedByteArray> pair in collection)
{
db_dictonary.Add(pair.Key.Data, pair.Value.Data);
}
return(db_dictonary
.OrderBy(x => x.Key, new UnsignedByteArrayCompare())
.Where(y => ByteUtil.Compare(y.Key, key) >= 0)
.Take((int)limit)
.Select(z => z.Value)
.ToList());
}
public byte[] Get(ISnapshot head, byte[] key)
{
ISnapshot snapshot = head;
Value result = null;
while (IsImplement(snapshot))
{
result = ((Snapshot)(snapshot)).db.Get(Key.Of(key));
if (result != null)
{
return(result.Data);
}
snapshot = snapshot.GetPrevious();
}
return(snapshot?.Get(key));
}
