private void SplitNode()
{
var splitIndex = (BranchingFactor - 1) / 2;
var left = this;
var right = new BPTreeNode <TKey, TData>(BranchingFactor);
var splitElem = _data.ElementAt(splitIndex);
left.MaxKey = _comparer.Decrement(splitElem.Key);
for (int i = _data.Count - 1; i > splitIndex; i--)
{
var elem = _data.ElementAt(i);
right.Insert(elem.Key, elem.Value);
_data.RemoveAt(i);
}
_data.RemoveAt(splitIndex);
foreach (var child in _children.Where(c => _comparer.Compare(c.MinKey, splitElem.Key) >= 0).ToList())
{
right.Children.Add(child);
child.Parent = right;
_children.Remove(child);
}
if (this.Parent == null)
{
this.Parent = new BPTreeNode <TKey, TData>(BranchingFactor);
this.Parent.InsertChildNode(left, splitElem.Key, splitElem.Value);
}
Parent.InsertChildNode(right, splitElem.Key, splitElem.Value);
}
public Index(IDataStorage dataStorage) : base(dataStorage)
{
Load();
if (_indexTree == null)
{
_indexTree = new BPTreeNode <TKey, DataItem>(15);
}
}
private void Load()
{
var dataBuffer = _dataStorage.ReadToEndOfAddressSpace(0);
if (dataBuffer != null && dataBuffer.Length > 0)
{
var json = ConvertBytesToData(dataBuffer);
var index = JsonConvert.DeserializeObject <BPTreeNode <TKey, DataItem> >(json);
index.InitialParentsOnNodes();
_indexTree = index;
}
}
private TKey FindMyMaxKey(BPTreeNode <TKey, TData> node)
{
var x = _children.SkipWhile(y => _comparer.Compare(y.MinKey, node.MinKey) <= 0).FirstOrDefault();
if (x == null || _comparer.Compare(x.MinKey, node.MinKey) == 0)
{
if (Parent != null)
{
return(Parent.FindMyMaxKey(node));
}
return(_comparer.MaxKey);
}
else
{
return(_comparer.Decrement(x.MinKey));
}
}
private void InsertChildNode(BPTreeNode <TKey, TData> node, TKey key, TData data)
{
_data[key] = data;
node.Parent = this;
var keyIndex = _data.IndexOfKey(key);
var grandChildKey = node.Data.Keys.FirstOrDefault();
if (_comparer.Compare(grandChildKey, key) < 0)
{
node.MaxKey = _comparer.Decrement(key);
if (keyIndex > 0)
{
node.MinKey = _data.Keys.ElementAt(--keyIndex);
}
else
{
node.MinKey = _comparer.MinKey;
}
}
else
{
node.MinKey = key;
if (keyIndex < _data.Count - 1)
{
node.MaxKey = _comparer.Decrement(_data.Keys.ElementAt(++keyIndex));
}
else
{
node.MaxKey = FindMyMaxKey(node);
}
}
_children.Add(node);
if (IsFull)
{
SplitNode();
}
}
public void Insert(DataKey key, DataItem value)
{
_indexTree = _indexTree.Insert(key.GetKey <TKey>(), value);
}
