/// <summary>
/// Find the bigger key in order to merger, or return null if this key is the biggest.
/// If keybytes == null, return the first key.
/// </summary>
/// <param name="keybytes"></param>
/// <param name="KeyArray"></param>
/// <returns></returns>
public static byte[] FindSmallestBiggerKey(byte[] keybytes, Dictionary <byte[], byte[]> KeyArray, IComparer <byte[]> comparer)
{
if (keybytes == null)
{
return(KeyFinder.FindFirstKey(KeyArray, comparer));
}
byte[] currentkey = null;
bool found = false;
foreach (var item in KeyArray)
{
if (comparer.Compare(item.Key, keybytes) > 0)
{
if (!found)
{
found = true;
currentkey = item.Key;
}
else
{
if (comparer.Compare(currentkey, item.Key) > 0)
{
currentkey = item.Key;
}
}
}
}
if (found)
{
return(currentkey);
}
else
{
return(null);
}
}
public static MemoryTreeNode FindFirstLeaf(TreeFile TreeFile, MemoryTreeNode currentNode = null)
{
if (currentNode == null)
{
currentNode = TreeFile.RootCache;
}
NodePointer pointer = new NodePointer();
pointer.PointerBytes = currentNode.TreeNode.PreviousPointer;
if (pointer.PositionPointer == 0)
{
var key = KeyFinder.FindFirstKey(currentNode.TreeNode.KeyArray, TreeFile.comparer);
if (key == null)
{
return(null);
}
pointer = currentNode.TreeNode.FindPointer(key);
}
if (pointer.PointerBytes != null && pointer.PositionPointer > 0 && pointer.Indicator != EnumValues.TypeIndicator.leaf)
{
var newcachenode = GetOrLoadNode(TreeFile, currentNode, pointer);
return(FindFirstLeaf(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);
}
