public static MemoryTreeNode FindLastLeaf(TreeFile TreeFile, MemoryTreeNode currentNode = null)
{
if (currentNode == null)
{
currentNode = TreeFile.RootCache;
}
NodePointer pointer = new NodePointer();
var key = KeyFinder.FindLastKey(currentNode.TreeNode.KeyArray, TreeFile.comparer);
if (key == null)
{
pointer.PointerBytes = currentNode.TreeNode.PreviousPointer;
}
else
{
pointer = currentNode.TreeNode.FindPointer(key);
}
if (pointer.PositionPointer > 0 && pointer.Indicator != EnumValues.TypeIndicator.leaf)
{
MemoryTreeNode newcachenode = GetOrLoadNode(TreeFile, currentNode, pointer);
return(FindLastLeaf(TreeFile, newcachenode));
}
///find the leaf that contains the key.
if (pointer.PointerBytes != null && pointer.PositionPointer > 0 && pointer.Indicator == EnumValues.TypeIndicator.leaf)
{
MemoryTreeNode newcacheleaf = GetOrLoadNode(TreeFile, currentNode, pointer);
return(newcacheleaf);
}
return(null);
}
public bool MoveNext()
{
///if in duplicate mode.
if (inDuplicateMode)
{
Int64 nextdup = duplicatereader.ReadNext();
if (nextdup > 0)
{
this.currentValue = nextdup;
return(true);
}
else
{
// end of duplicate.
this.inDuplicateMode = false;
this.duplicatereader = null;
// cotinue with the getnextpointer;
}
}
NodePointer pointer = getnextpointer();
if (pointer == null)
{
return(false);
}
/// else
///
if (pointer.Indicator == EnumValues.TypeIndicator.block)
{
this.currentValue = pointer.PositionPointer;
return(true);
}
else if (pointer.Indicator == EnumValues.TypeIndicator.duplicate)
{
duplicatereader = this.treefile.duplicate.getReader(pointer.PositionPointer);
Int64 nextdup = duplicatereader.ReadNext();
if (nextdup > 0)
{
this.currentValue = nextdup;
this.inDuplicateMode = true;
return(true);
}
else
{
// there is no item in the duplicate, should not be possible, just to make sure.
this.duplicatereader = null;
this.inDuplicateMode = false;
// go to the next record again.
return(MoveNext());
}
}
else
{
/// should not be possible.
return(false);
}
}
/// <summary>
/// load the record, this is in the DESC mode.
/// </summary>
/// <param name="currentnode"></param>
private void loadNodeRecordDESC(MemoryTreeNode currentnode)
{
//recordIndex = -1;
//recordlistcount = 0;
//recordlist.Clear();
foreach (var item in currentnode.TreeNode.KeyArray.OrderByDescending(o => o.Key, this.comparer))
{
if (isCurrentStartNode)
{
if (isCurrentEndNode)
{
//both start and end in the same leaf.
if ((this.comparer.Compare(startKeyBytes, item.Key) < 0 || (this.comparer.Compare(startKeyBytes, item.Key) == 0 && !this.lowerOpen)) && (this.comparer.Compare(endKeyBytes, item.Key) > 0 || (this.comparer.Compare(endKeyBytes, item.Key) == 0 && !this.upperOpen)))
{
NodePointer pointer = new NodePointer();
pointer.PointerBytes = item.Value;
recordlist.Add(pointer);
}
}
else
{
// the start node.
if (this.comparer.Compare(endKeyBytes, item.Key) > 0 || (this.comparer.Compare(endKeyBytes, item.Key) == 0 && !this.upperOpen))
{
NodePointer pointer = new NodePointer();
pointer.PointerBytes = item.Value;
recordlist.Add(pointer);
}
}
}
else
{
// the end node.
if (isCurrentEndNode)
{
if (this.comparer.Compare(startKeyBytes, item.Key) < 0 || (this.comparer.Compare(startKeyBytes, item.Key) == 0 && !this.lowerOpen))
{
NodePointer pointer = new NodePointer();
pointer.PointerBytes = item.Value;
recordlist.Add(pointer);
}
}
else
{
//not start, not end, the middle one, insert everything.
NodePointer pointer = new NodePointer();
pointer.PointerBytes = item.Value;
recordlist.Add(pointer);
}
}
}
recordlistcount = recordlist.Count;
}
private static MemoryTreeNode FindContainerLastLeaf(TreeFile TreeFile, MemoryTreeNode ContainerNode)
{
if (ContainerNode == null)
{
return(null);
}
if (ContainerNode.TreeNode.TypeIndicator == EnumValues.TypeIndicator.leaf)
{
return(ContainerNode);
}
NodePointer pointer = new NodePointer();
pointer.PointerBytes = ContainerNode.TreeNode.PreviousPointer;
if (pointer.PositionPointer > 0)
{
var subnode = GetOrLoadNode(TreeFile, ContainerNode, pointer);
if (subnode != null)
{
var result = FindContainerFirstLeaf(TreeFile, subnode);
if (result != null)
{
return(result);
}
}
}
// did not get return, try one key by one key.
byte[] key = KeyFinder.FindSmallestBiggerKey(null, ContainerNode.TreeNode.KeyArray, TreeFile.comparer);
while (key != null)
{
var nodepointer = ContainerNode.TreeNode.FindPointer(key);
if (nodepointer != null && nodepointer.PositionPointer > 0)
{
var keynode = GetOrLoadNode(TreeFile, ContainerNode, nodepointer);
if (keynode != null)
{
var result = FindContainerFirstLeaf(TreeFile, keynode);
if (result != null)
{
return(result);
}
}
}
key = KeyFinder.FindSmallestBiggerKey(key, ContainerNode.TreeNode.KeyArray, TreeFile.comparer);
}
return(null);
}
private static MemoryTreeNode GetUpLinkLastLeaf(TreeFile TreeFile, MemoryTreeNode ParentNode)
{
if (ParentNode.TreeNode.TypeIndicator == EnumValues.TypeIndicator.root)
{
return(null);
}
MemoryTreeNode siblingNode;
byte[] siblingkey = KeyFinder.FindBiggestSmallerKey(ParentNode.ParentNodeKey, ParentNode.Parent.TreeNode.KeyArray, TreeFile.comparer);
while (siblingkey != null)
{
var pointer = ParentNode.Parent.TreeNode.FindPointer(siblingkey);
if (pointer != null && pointer.PositionPointer > 0)
{
siblingNode = GetOrLoadNode(TreeFile, ParentNode.Parent, pointer);
var result = FindContainerLastLeaf(TreeFile, siblingNode);
if (result != null)
{
return(result);
}
}
siblingkey = KeyFinder.FindBiggestSmallerKey(siblingkey, ParentNode.Parent.TreeNode.KeyArray, TreeFile.comparer);
}
/// need to check the first previous pointer after process all key arrays.
NodePointer previousPointer = new NodePointer();
previousPointer.PointerBytes = ParentNode.Parent.TreeNode.PreviousPointer;
var PreviousPointerNode = GetOrLoadNode(TreeFile, ParentNode.Parent, previousPointer);
//parentNode.Parent.PreviousPointerNode can't be the same with ParentNode,otherwise it will cause a dead cycle.
if (PreviousPointerNode != null && ParentNode != PreviousPointerNode)
{
var result = FindContainerLastLeaf(TreeFile, PreviousPointerNode);
if (result != null)
{
return(result);
}
}
return(GetUpLinkLastLeaf(TreeFile, ParentNode.Parent));
}
/// <summary>
/// find the pointer to next node or leaf that should contains the key.
/// </summary>
/// <param name="key"></param>
/// <returns></returns>
public NodePointer FindPointer(byte[] key)
{
NodePointer nodepointer = new NodePointer();
byte[] currentkey = key;
byte[] currentvalue = new byte[NodePointer.Length];
bool found = false;
foreach (var item in KeyArray)
{
if (this.tree.comparer.Compare(key, item.Key) >= 0)
{
if (!found)
{
found = true;
currentkey = item.Key;
currentvalue = item.Value;
}
else
{
if (this.tree.comparer.Compare(item.Key, currentkey) > 0)
{
currentkey = item.Key;
currentvalue = item.Value;
}
}
}
}
if (found)
{
nodepointer.KeyToPosition = currentkey;
nodepointer.PointerBytes = currentvalue;
}
else
{
nodepointer.PointerBytes = this.PreviousPointer;
nodepointer.IsFirstPreviousPointer = true;
}
return(nodepointer);
}
public static MemoryTreeNode FindPreviousLeaf(TreeFile TreeFile, MemoryTreeNode CurrentLeaf)
{
if (CurrentLeaf.TreeNode.TypeIndicator != EnumValues.TypeIndicator.leaf)
{
throw new Exception("this method only accept leaf");
}
if (CurrentLeaf.IsParentPreviousPointer && CurrentLeaf.ParentNodeKey == null)
{
return(GetUpLinkLastLeaf(TreeFile, CurrentLeaf.Parent));
}
byte[] key = KeyFinder.FindBiggestSmallerKey(CurrentLeaf.ParentNodeKey, CurrentLeaf.Parent.TreeNode.KeyArray, TreeFile.comparer);
while (key != null)
{
var pointer = CurrentLeaf.Parent.TreeNode.FindPointer(key);
if (pointer != null && pointer.PositionPointer > 0)
{
var nextleaf = GetOrLoadNode(TreeFile, CurrentLeaf.Parent, pointer);
if (nextleaf != null && nextleaf.TreeNode.TypeIndicator == EnumValues.TypeIndicator.leaf)
{
return(nextleaf);
}
}
key = KeyFinder.FindBiggestSmallerKey(key, CurrentLeaf.Parent.TreeNode.KeyArray, TreeFile.comparer);
}
// check the previous pointer.
NodePointer previousPointer = new NodePointer();
previousPointer.PointerBytes = CurrentLeaf.Parent.TreeNode.PreviousPointer;
var PreviousPointerLeaf = GetOrLoadNode(TreeFile, CurrentLeaf.Parent, previousPointer);
if (PreviousPointerLeaf != null && PreviousPointerLeaf.TreeNode.TypeIndicator == EnumValues.TypeIndicator.leaf)
{
return(PreviousPointerLeaf);
}
return(GetUpLinkLastLeaf(TreeFile, CurrentLeaf.Parent));
}
/// <summary>
/// Find by key, return the lowerest node...
/// </summary>
/// <param name="currentNode"></param>
/// <param name="Key"></param>
/// <returns></returns>
public static MemoryTreeNode FindLeafByKey(TreeFile Tree, MemoryTreeNode currentNode, byte[] Keybytes)
{
NodePointer pointer = currentNode.TreeNode.FindPointer(Keybytes);
if (pointer.PositionPointer == 0)
{
Tree.CreateFirstLeaf(currentNode.TreeNode);
NodeChange(Tree, currentNode);
return(FindLeafByKey(Tree, Tree.RootCache, Keybytes));
}
MemoryTreeNode foundnode = GetOrLoadNode(Tree, currentNode, pointer);
if (foundnode.TreeNode.TypeIndicator == EnumValues.TypeIndicator.leaf)
{
return(foundnode);
}
else
{
return(FindLeafByKey(Tree, foundnode, Keybytes));
}
}
public static MemoryTreeNode GetOrLoadNode(TreeFile TreeFile, MemoryTreeNode ParentNode, NodePointer Pointer)
{
if (Pointer.IsFirstPreviousPointer)
{
if (ParentNode.PreviousPointer != null)
{
return(ParentNode.PreviousPointer);
}
else
{
TreeNode node = TreeFile.ReadNode(Pointer.PositionPointer);
if (node == null)
{
return(null);
}
MemoryTreeNode newcachenode = new MemoryTreeNode(node);
newcachenode.Parent = ParentNode;
newcachenode.IsParentPreviousPointer = Pointer.IsFirstPreviousPointer;
newcachenode.ParentNodeKey = Pointer.KeyToPosition;
newcachenode.Level = ParentNode.Level + 1;
if (newcachenode.Level < TreeFile.MaxCacheLevel)
{
ParentNode.PreviousPointer = newcachenode;
}
return(newcachenode);
}
}
else
{
if (ParentNode.Children.ContainsKey(Pointer.PositionPointer))
{
return(ParentNode.Children[Pointer.PositionPointer]);
}
else
{
TreeNode node = TreeFile.ReadNode(Pointer.PositionPointer);
if (node == null)
{
return(null);
}
MemoryTreeNode newcachenode = new MemoryTreeNode(node);
newcachenode.Parent = ParentNode;
newcachenode.IsParentPreviousPointer = Pointer.IsFirstPreviousPointer;
newcachenode.ParentNodeKey = Pointer.KeyToPosition;
newcachenode.Level = ParentNode.Level + 1;
if (newcachenode.Level < TreeFile.MaxCacheLevel)
{
ParentNode.Children[Pointer.PositionPointer] = newcachenode;
}
return(newcachenode);
}
}
}
/// <summary>
/// Get the count of records in the range. count distinct will have better performance.
/// </summary>
/// <param name="range"></param>
/// <param name="distinct"></param>
/// <returns></returns>
public int Count(Range <T> range, bool distinct)
{
lock (_object)
{
byte[] startKeyBytes = this.Converter.ToByte(range.lower);
byte[] endKeyBytes = this.Converter.ToByte(range.upper);
startKeyBytes = this.appendToFixedLength(startKeyBytes);
endKeyBytes = this.appendToFixedLength(endKeyBytes);
MemoryTreeNode startnode = MemoryTreeNodeManager.FindLeafByKey(this.Tree, this.Tree.RootCache, startKeyBytes);
MemoryTreeNode endnode = MemoryTreeNodeManager.FindLeafByKey(this.Tree, this.Tree.RootCache, endKeyBytes);
if (startnode.TreeNode.DiskPosition == endnode.TreeNode.DiskPosition)
{
int count = 0;
foreach (var item in startnode.TreeNode.KeyArray)
{
if ((this.Comparer.Compare(startKeyBytes, item.Key) < 0 || (this.Comparer.Compare(startKeyBytes, item.Key) == 0 && !range.lowerOpen)) && ((this.Comparer.Compare(endKeyBytes, item.Key) > 0 || (this.Comparer.Compare(endKeyBytes, item.Key) == 0 && !range.upperOpen))))
{
if (!distinct)
{
NodePointer pointer = new NodePointer();
pointer.PointerBytes = item.Value;
if (pointer.Indicator == EnumValues.TypeIndicator.duplicate)
{
count = count + this.Tree.duplicate.count(pointer.PositionPointer);
}
else
{
count += 1;
}
}
else
{
count += 1;
}
}
}
return(count);
}
else
{
int firstnodecount = 0;
int lastnodecount = 0;
int middlecount = 0;
foreach (var item in startnode.TreeNode.KeyArray)
{
if (this.Comparer.Compare(startKeyBytes, item.Key) < 0 || (this.Comparer.Compare(startKeyBytes, item.Key) == 0 && !range.lowerOpen))
{
if (!distinct)
{
NodePointer pointer = new NodePointer();
pointer.PointerBytes = item.Value;
if (pointer.Indicator == EnumValues.TypeIndicator.duplicate)
{
firstnodecount = firstnodecount + this.Tree.duplicate.count(pointer.PositionPointer);
}
else
{
firstnodecount += 1;
}
}
else
{
firstnodecount += 1;
}
}
}
foreach (var item in endnode.TreeNode.KeyArray)
{
if (this.Comparer.Compare(endKeyBytes, item.Key) > 0 || (this.Comparer.Compare(endKeyBytes, item.Key) == 0 && !range.upperOpen))
{
if (!distinct)
{
NodePointer pointer = new NodePointer();
pointer.PointerBytes = item.Value;
if (pointer.Indicator == EnumValues.TypeIndicator.duplicate)
{
lastnodecount = lastnodecount + this.Tree.duplicate.count(pointer.PositionPointer);
}
else
{
lastnodecount += 1;
}
}
else
{
lastnodecount += 1;
}
}
}
var middlenode = MemoryTreeNodeManager.FindNextLeaf(this.Tree, startnode);
while (middlenode.TreeNode.DiskPosition != endnode.TreeNode.DiskPosition)
{
foreach (var item in middlenode.TreeNode.KeyArray)
{
if (!distinct)
{
NodePointer pointer = new NodePointer();
pointer.PointerBytes = item.Value;
if (pointer.Indicator == EnumValues.TypeIndicator.duplicate)
{
middlecount = middlecount + this.Tree.duplicate.count(pointer.PositionPointer);
}
else
{
middlecount += 1;
}
}
else
{
middlecount += 1;
}
}
middlenode = MemoryTreeNodeManager.FindNextLeaf(this.Tree, middlenode);
}
return(firstnodecount + middlecount + lastnodecount);
}
}
}