/// <summary>
/// Removes key-value pair by key.
/// </summary>
/// <param name="key">The key</param>
public void Remove(TKey key)
{
var leafNode = GetSuitableLeafNodeForKeyIfRangeExists(key);
if (leafNode == null)
{
return;
}
int index;
var entry = FindSuitableEntry(leafNode.Entries, key, out index);
if (entry.HasValue)
{
// free referenced value
_valueStorage.Free(leafNode.Entries[index].Value);
// delete reference from node
leafNode.Entries.RemoveAt(index);
if (IsSufficientlyFilled(leafNode))
{
_nodeStorage.Update(leafNode);
return;
}
var nodesToUpdate = new Dictionary <long, IBPlusTreeNode <TKey> >();
CombineIfNeeded(leafNode, nodesToUpdate);
foreach (var nodeToUpdate in nodesToUpdate)
{
_nodeStorage.Update(nodeToUpdate.Value);
}
}
}
/// <summary>
/// Removes key-value pair by key.
/// </summary>
/// <param name="key">The key</param>
public void Remove(TKey key)
{
var binaryKey = _keySerializer.Serialize(key);
int keyOffset;
int nodePrefixOffset;
bool isFullMatch;
IRadixTreeNode node = FindMostSuitableNode(binaryKey, out keyOffset, out nodePrefixOffset, out isFullMatch);
if (isFullMatch)
{
_valueStorage.Free(node.ValueReference);
node.ValueReference = null;
if (node.Entries.Any())
{
if (node.Prefix != null && node.Entries.Count == 1)
{
var child = _nodeStorage.Fetch(node.Entries[0].Value);
var newPrefixLength = node.Prefix.Length + child.Prefix.Length;
if (newPrefixLength <= MaxPrefixLength)
{
var newPrefix = new byte[newPrefixLength];
Buffer.BlockCopy(node.Prefix, 0, newPrefix, 0, node.Prefix.Length);
Buffer.BlockCopy(child.Prefix, 0, newPrefix, node.Prefix.Length, child.Prefix.Length);
child.Prefix = newPrefix;
child.ParentNodeReference = node.ParentNodeReference;
_nodeStorage.Remove(node.Reference);
bool reallocated;
child = UpdateOrReallocateNode(child, out reallocated);
var parent = _nodeStorage.Fetch(child.ParentNodeReference);
int index;
FindSuitableEntry(parent.Entries, child.Prefix[0], out index);
parent.Entries[index] = new KeyValuePair <byte, DbItemReference>(child.Prefix[0], child.Reference);
UpdateOrFail(parent);
}
else
{
UpdateOrFail(node);
}
}
else
{
UpdateOrFail(node);
}
}
else
{
while (!DbItemReference.IsNull(node.ParentNodeReference))
{
var parentNode = _nodeStorage.Fetch(node.ParentNodeReference);
int index;
FindSuitableEntry(parentNode.Entries, node.Prefix[0], out index);
parentNode.Entries.RemoveAt(index);
_nodeStorage.Remove(node.Reference);
if (parentNode.Entries.Any() || parentNode.ValueReference != null ||
DbItemReference.IsNull(parentNode.ParentNodeReference))
{
UpdateOrFail(parentNode);
break;
}
node = parentNode;
}
}
}
}
