public override string ToString()
{
var builder = new StringBuilder();
BTreeNodeElement <T> start = FirstElement;
while (start != null)
{
builder.Append(start + " - ");
start = start.Next;
}
builder.Append(string.Format("self = {0}, parent = {1}", identifier,
Parent == null ? "NULL" : Parent.Identifier.ToString()));
builder.AppendLine();
BTreeNodeElementInterstice <T> startInterstice = FirstInterstice;
while (startInterstice != null)
{
if (!(startInterstice.NodePointer is NullBTreeNode <T>))
{
builder.AppendLine(startInterstice.NodePointer.ToString());
}
startInterstice = startInterstice.Next;
}
return(builder.ToString());
}
private void InsertInCurrentNode(BTreeNodeElement <T> element)
{
if (firstInterstice == null)
{
element.PreviousInterval.Smaller = null;
element.NextInterval.Larger = null;
firstInterstice = element.PreviousInterval;
element.PreviousInterval.Container = element.NextInterval.Container = this;
return;
}
BTreeNodeElementInterstice <T> insertionInterstice = IntersticeToSearch(element.Value);
if (insertionInterstice.Smaller != null)
{
insertionInterstice.Smaller.NextInterval = element.PreviousInterval;
}
if (insertionInterstice.Larger != null)
{
insertionInterstice.Larger.PreviousInterval = element.NextInterval;
}
element.PreviousInterval.Smaller = insertionInterstice.Smaller;
element.NextInterval.Larger = insertionInterstice.Larger;
if (insertionInterstice == firstInterstice)
{
firstInterstice = element.PreviousInterval;
}
}
public void Insert(T value)
{
var element = new BTreeNodeElement <T>(value);
element.PreviousInterval = new BTreeNodeElementInterstice <T>(null, element);
element.NextInterval = new BTreeNodeElementInterstice <T>(element, null);
InternalInsert(element);
}
private bool Equals(BTreeNodeElement <T> other)
{
if (ReferenceEquals(null, other))
{
return(false);
}
if (ReferenceEquals(this, other))
{
return(true);
}
return(Equals(other.value, value));
}
private BTreeNode <T> DissectedNodeFrom(BTreeNodeElement <T> element)
{
BTreeNodeElement <T> start = element;
var node = new BTreeNode <T>(order, tree);
while (start != null)
{
node.Insert(start);
start = start.Next;
}
return(node);
}
private BTreeNodeElement <T> ElementAt(int index)
{
BTreeNodeElement <T> start = FirstElement;
int i = 0;
while (i < index)
{
start = start.NextInterval.Larger;
++i;
}
return(start);
}
private void Promote(BTreeNodeElement <T> elementToPromote, BTreeNode <T> smallerNode, BTreeNode <T> largerNode)
{
if (Parent == null)
{
Parent = new BTreeNode <T>(order, tree);
tree.RootIs(Parent);
}
elementToPromote.NextInterval.Container = elementToPromote.PreviousInterval.Container = Parent;
elementToPromote.PreviousInterval.NodePointer = smallerNode;
elementToPromote.NextInterval.NodePointer = largerNode;
Parent.Insert(elementToPromote);
}
private void Insert(BTreeNodeElement <T> element)
{
var copiedElement = new BTreeNodeElement <T>(element.Value);
copiedElement.PreviousInterval = new BTreeNodeElementInterstice <T>(element.PreviousInterval.NodePointer,
null, copiedElement);
copiedElement.NextInterval = new BTreeNodeElementInterstice <T>(element.NextInterval.NodePointer,
copiedElement,
null);
copiedElement.PreviousInterval.NodePointer.Parent = copiedElement.NextInterval.NodePointer.Parent = this;
InternalInsert(copiedElement);
}
public BTreeNodeElement <T> Search(T value)
{
BTreeNodeElement <T> element = ElementContaining(value);
if (element != null)
{
return(element);
}
BTreeNodeElementInterstice <T> interstice = IntersticeToSearch(value);
if (interstice == null || interstice.NodePointer is NullBTreeNode <T> )
{
return(new NullBTreeNodeElement <T>());
}
return(interstice.NodePointer.Search(value));
}
public BTreeNode <T> Find(T value)
{
BTreeNodeElement <T> node = ElementContaining(value);
if (node != null)
{
return(this);
}
BTreeNodeElementInterstice <T> interstice = IntersticeToSearch(value);
if (interstice == null || interstice.NodePointer is NullBTreeNode <T> )
{
return(this);
}
return(interstice.NodePointer.Find(value));
}
private BTreeNodeElement <T> ElementContaining(T value)
{
if (firstInterstice == null)
{
return(null);
}
BTreeNodeElement <T> element = firstInterstice.Larger;
while (element != null)
{
if (element.Value.Equals(value))
{
return(element);
}
element = element.Next;
}
return(null);
}
private void InternalInsert(BTreeNodeElement <T> element)
{
InsertInCurrentNode(element);
if (Count <= order)
{
return;
}
int indexOfValueToPromote = (int)Math.Round((double)Count / 2) - 1;
BTreeNodeElement <T> elementToPromote = ElementAt(indexOfValueToPromote);
Console.Out.WriteLine("{0} will be promoted", elementToPromote.Value);
BTreeNode <T> node = DissectedNodeFrom(elementToPromote.Next);
if (!(FirstInterstice.NodePointer is NullBTreeNode <T>))
{
elementToPromote.Previous.BreakForwardLink();
}
elementToPromote.TerminateForwardLink();
var promotedReplica = new BTreeNodeElement <T>(elementToPromote.Value);
Promote(promotedReplica, this, node);
}
public BTreeNodeElementInterstice(BTreeNode <T> pointer, BTreeNodeElement <T> smaller, BTreeNodeElement <T> larger)
{
Smaller = smaller;
Larger = larger;
NodePointer = pointer;
}
public BTreeNodeElementInterstice(BTreeNodeElement <T> smaller, BTreeNodeElement <T> larger)
: this(new NullBTreeNode <T>(), smaller, larger)
{
}