/// <summary>
/// <pre>
/// 1 take median element
/// 2 insert the median in the parent (shifting necessary elements)
/// 3 create a new node with right part elements (moving keys and values and children)
/// 4 set this new node as a child of parent
/// </pre>
/// </summary>
public virtual void Split(NeoDatis.Btree.IBTreeNode parent, NeoDatis.Btree.IBTreeNode
node2Split, int childIndex)
{
// BTreeValidator.validateNode(parent, parent == root);
// BTreeValidator.validateNode(node2Split, false);
// 1
NeoDatis.Btree.IKeyAndValue median = node2Split.GetMedian();
// 2
parent.SetKeyAndValueAt(median, childIndex, true, true);
// 3
NeoDatis.Btree.IBTreeNode rightPart = node2Split.ExtractRightPart();
// 4
parent.SetChildAt(rightPart, childIndex + 1);
parent.SetChildAt(node2Split, childIndex);
parent.IncrementNbChildren();
persister.SaveNode(parent);
persister.SaveNode(rightPart);
persister.SaveNode(node2Split);
if (NeoDatis.Btree.Tool.BTreeValidator.IsOn())
{
NeoDatis.Btree.Tool.BTreeValidator.ValidateNode(parent, parent == root);
NeoDatis.Btree.Tool.BTreeValidator.ValidateNode(rightPart, false);
NeoDatis.Btree.Tool.BTreeValidator.ValidateNode(node2Split, false);
}
}
public virtual NeoDatis.Btree.IKeyAndValue GetBiggest(NeoDatis.Btree.IBTreeNode node
, bool delete)
{
int lastKeyIndex = node.GetNbKeys() - 1;
int lastChildIndex = node.GetNbChildren() - 1;
if (lastChildIndex > lastKeyIndex)
{
NeoDatis.Btree.IBTreeNode child = node.GetChildAt(lastChildIndex, true);
if (child.GetNbKeys() == degree - 1)
{
node = PrepareForDelete(node, child, lastChildIndex);
}
lastChildIndex = node.GetNbChildren() - 1;
child = node.GetChildAt(lastChildIndex, true);
return(GetBiggest(child, delete));
}
NeoDatis.Btree.IKeyAndValue kav = node.GetKeyAndValueAt(lastKeyIndex);
if (delete)
{
node.DeleteKeyAndValueAt(lastKeyIndex, false);
persister.SaveNode(node);
}
return(kav);
}
protected virtual T NextAsc()
{
// Try to go down till a leaf
while (!currentNode.IsLeaf())
{
currentNode = currentNode.GetChildAt(currentKeyIndex, true);
currentKeyIndex = 0;
}
// If leaf has more keys
if (currentKeyIndex < currentNode.GetNbKeys())
{
nbReturnedKeys++;
nbReturnedElements++;
object nodeValue = GetValueAt(currentNode, currentKeyIndex);
currentKeyIndex++;
return((T)nodeValue);
}
NeoDatis.Btree.IBTreeNode child = null;
// else go up till a node with keys
while (currentKeyIndex >= currentNode.GetNbKeys())
{
child = currentNode;
currentNode = currentNode.GetParent();
currentKeyIndex = IndexOfChild(currentNode, child);
}
nbReturnedElements++;
nbReturnedKeys++;
object value = GetValueAt(currentNode, currentKeyIndex);
currentKeyIndex++;
return((T)value);
}
// Commented by Olivier 05/11/2007
// persister.flush();
private void InsertNonFull(NeoDatis.Btree.IBTreeNode node, System.IComparable key
, object value)
{
if (node.IsLeaf())
{
node.InsertKeyAndValue(key, value);
persister.SaveNode(node);
return;
}
int position = node.GetPositionOfKey(key);
// return an index starting
// from 1 instead of 0
int realPosition = -position - 1;
// If position is positive, the key must be inserted in this node
if (position >= 0)
{
realPosition = position - 1;
node.InsertKeyAndValue(key, value);
persister.SaveNode(node);
return;
}
// descend
NeoDatis.Btree.IBTreeNode nodeToDescend = node.GetChildAt(realPosition, true);
if (nodeToDescend.IsFull())
{
Split(node, nodeToDescend, realPosition);
if (node.GetKeyAt(realPosition).CompareTo(key) < 0)
{
nodeToDescend = node.GetChildAt(realPosition + 1, true);
}
}
InsertNonFull(nodeToDescend, key, value);
}
public virtual NeoDatis.Btree.IBTree LoadBTree(object id)
{
nbLoadTree++;
NeoDatis.Odb.OID oid = (NeoDatis.Odb.OID)id;
try
{
if (NeoDatis.Odb.OdbConfiguration.IsDebugEnabled(LogId))
{
NeoDatis.Tool.DLogger.Debug("Loading btree with id " + oid);
}
if (oid == NeoDatis.Odb.Impl.Core.Layers.Layer3.Engine.StorageEngineConstant.NullObjectId)
{
throw new NeoDatis.Odb.ODBRuntimeException(NeoDatis.Btree.BTreeError.InvalidIdForBtree
.AddParameter(NeoDatis.Odb.Impl.Core.Layers.Layer3.Engine.StorageEngineConstant.
NullObjectId));
}
tree = (NeoDatis.Btree.IBTree)engine.GetObjectFromOid(oid);
tree.SetId(oid);
tree.SetPersister(this);
NeoDatis.Btree.IBTreeNode root = tree.GetRoot();
root.SetBTree(tree);
return(tree);
}
catch (System.Exception e)
{
throw new NeoDatis.Odb.ODBRuntimeException(NeoDatis.Btree.BTreeError.InternalError
, e);
}
}
public override object GetValueAt(NeoDatis.Btree.IBTreeNode node, int currentIndex
)
{
NeoDatis.Btree.IBTreeNodeOneValuePerKey n = (NeoDatis.Btree.IBTreeNodeOneValuePerKey
)node;
return(n.GetValueAt(currentIndex));
}
public AbstractBTree()
{
this.degree = 0;
this.size = 0;
this.height = 1;
this.persister = null;
root = null;
}
public override void SetChildAt(NeoDatis.Btree.IBTreeNode child, int index)
{
children[index] = child;
if (child != null)
{
child.SetParent(this);
}
}
public override void Clear()
{
base.Clear();
parent = null;
parentOid = null;
childrenOids = null;
oid = null;
}
public override NeoDatis.Btree.IBTreeNode GetParent()
{
if (parent != null)
{
return parent;
}
parent = btree.GetPersister().LoadNodeById(parentOid);
return parent;
}
public override NeoDatis.Btree.IBTreeNode GetParent()
{
if (parent != null)
{
return(parent);
}
parent = btree.GetPersister().LoadNodeById(parentOid);
return(parent);
}
public override void SetChildAt(NeoDatis.Btree.IBTreeNode node, int childIndex, int
index, bool throwExceptionIfDoesNotExist)
{
NeoDatis.Btree.IBTreeNode child = node.GetChildAt(childIndex, throwExceptionIfDoesNotExist
);
children[index] = child;
if (child != null)
{
child.SetParent(this);
}
}
public virtual System.Text.StringBuilder Build(NeoDatis.Btree.IBTreeNode node, int
height, bool withIds)
{
lines = new System.Text.StringBuilder[height];
for (int i = 0; i < height; i++)
{
lines[i] = new System.Text.StringBuilder();
}
BuildDisplay(node, 0, 0, "0", withIds);
BuildRepresentation();
return(result);
}
/// <summary>Creates a new node with the right part of this node.</summary>
/// <remarks>
/// Creates a new node with the right part of this node. This should only be
/// called on a full node
/// </remarks>
public virtual NeoDatis.Btree.IBTreeNode ExtractRightPart()
{
if (!IsFull())
{
throw new NeoDatis.Btree.Exception.BTreeException("extract right part called on non full node"
);
}
// Creates an empty new node
NeoDatis.Btree.IBTreeNode rightPart = btree.BuildNode();
int j = 0;
for (int i = degree; i < maxNbKeys; i++)
{
rightPart.SetKeyAndValueAt(keys[i], values[i], j, false, false);
keys[i] = null;
values[i] = null;
rightPart.SetChildAt(this, i, j, false);
// TODO must we load all nodes to set new parent
NeoDatis.Btree.IBTreeNode c = rightPart.GetChildAt(j, false);
if (c != null)
{
c.SetParent(rightPart);
}
// rightPart.setChildAt(getChildAt(i,false), j);
SetNullChildAt(i);
j++;
}
// rightPart.setChildAt(getLastPositionChild(), j);
rightPart.SetChildAt(this, GetMaxNbChildren() - 1, j, false);
// correct father id
NeoDatis.Btree.IBTreeNode c1 = rightPart.GetChildAt(j, false);
if (c1 != null)
{
c1.SetParent(rightPart);
}
SetNullChildAt(maxNbChildren - 1);
// resets last child
keys[degree - 1] = null;
// resets median element
values[degree - 1] = null;
// set numbers
nbKeys = degree - 1;
int originalNbChildren = nbChildren;
nbChildren = System.Math.Min(nbChildren, degree);
rightPart.SetNbKeys(degree - 1);
rightPart.SetNbChildren(originalNbChildren - nbChildren);
NeoDatis.Btree.Tool.BTreeValidator.ValidateNode(this);
NeoDatis.Btree.Tool.BTreeValidator.ValidateNode(rightPart);
NeoDatis.Btree.Tool.BTreeValidator.CheckDuplicateChildren(this, rightPart);
return(rightPart);
}
private int IndexOfChild(NeoDatis.Btree.IBTreeNode parent, NeoDatis.Btree.IBTreeNode
child)
{
for (int i = 0; i < parent.GetNbChildren(); i++)
{
if (parent.GetChildAt(i, true).GetId() == child.GetId())
{
return(i);
}
}
throw new System.Exception("parent " + parent + " does not have the specified child : "
+ child);
}
public override void SetChildAt(NeoDatis.Btree.IBTreeNode node, int childIndex, int
indexDestination, bool throwExceptionIfDoesNotExist)
{
NeoDatis.Odb.OID childOid = (NeoDatis.Odb.OID)node.GetChildIdAt(childIndex, throwExceptionIfDoesNotExist
);
childrenOids[indexDestination] = childOid;
if (childOid != null)
{
// The parent of the child has changed
NeoDatis.Btree.IBTreeNode child = btree.GetPersister().LoadNodeById(childOid);
child.SetParent(this);
btree.GetPersister().SaveNode(child);
}
}
// TODO Auto-generated method stub
public override void Reset()
{
this.currentNode = btree.GetRoot();
if (orderByType.IsOrderByDesc())
{
this.currentKeyIndex = currentNode.GetNbKeys();
}
else
{
this.currentKeyIndex = 0;
}
nbReturnedElements = 0;
nbReturnedKeys = 0;
}
public AbstractBTreeIterator(NeoDatis.Btree.IBTree tree, NeoDatis.Odb.Core.OrderByConstants
orderByType)
{
this.btree = tree;
this.currentNode = tree.GetRoot();
this.orderByType = orderByType;
if (orderByType.IsOrderByDesc())
{
this.currentKeyIndex = currentNode.GetNbKeys();
}
else
{
this.currentKeyIndex = 0;
}
}
public virtual object DeleteNode(NeoDatis.Btree.IBTreeNode o)
{
NeoDatis.Odb.OID oid = engine.Delete(o);
oids.Remove(oid);
int position = modifiedObjectOids.Remove2(oid);
//TODO
if (position != null)
{
// Just replace the element by null, to not modify all the other
// positions
modifiedObjectOidList.Set(position, null);
}
return(o);
}
public AbstractBTree(string name, int degree, NeoDatis.Btree.IBTreePersister persister
)
{
this.name = name;
this.degree = degree;
this.size = 0;
this.height = 1;
this.persister = persister;
root = BuildNode();
// TODO check if it is needed to store the root before the btree ->
// saving btree will try to update root!
persister.SaveNode(root);
persister.SaveBTree(this);
persister.Flush();
}
private void BuildDisplay(NeoDatis.Btree.IBTreeNode node, int currentHeight, int
childIndex, object parentId, bool withIds)
{
if (currentHeight > lines.Length - 1)
{
return;
}
// get string buffer of this line
System.Text.StringBuilder line = lines[currentHeight];
if (withIds)
{
line.Append(node.GetId()).Append(":[");
}
else
{
line.Append("[");
}
for (int i = 0; i < node.GetNbKeys(); i++)
{
if (i > 0)
{
line.Append(" , ");
}
NeoDatis.Btree.IKeyAndValue kav = node.GetKeyAndValueAt(i);
line.Append(kav.GetKey());
}
if (withIds)
{
line.Append("]:").Append(node.GetParentId()).Append("/").Append(parentId).Append(
" ");
}
else
{
line.Append("] ");
}
for (int i = 0; i < node.GetNbChildren(); i++)
{
NeoDatis.Btree.IBTreeNode child = node.GetChildAt(i, false);
if (child != null)
{
BuildDisplay(child, currentHeight + 1, i, node.GetId(), withIds);
}
else
{
lines[currentHeight + 1].Append("[Child " + (i + 1) + " null!] ");
}
}
}
public override void SetChildAt(NeoDatis.Btree.IBTreeNode child, int index)
{
if (child != null)
{
if (child.GetId() == null)
{
btree.GetPersister().SaveNode(child);
}
childrenOids[index] = (NeoDatis.Odb.OID)child.GetId();
child.SetParent(this);
}
else
{
childrenOids[index] = null;
}
}
public override void SetParent(NeoDatis.Btree.IBTreeNode node)
{
parent = node;
if (parent != null)
{
if (parent.GetId() == null)
{
btree.GetPersister().SaveNode(parent);
}
parentOid = (NeoDatis.Odb.OID)parent.GetId();
}
else
{
parentOid = null;
}
}
public override void SetParent(NeoDatis.Btree.IBTreeNode node)
{
parent = node;
if (parent != null)
{
if (parent.GetId() == null)
{
btree.GetPersister().SaveNode(parent);
}
parentOid = (NeoDatis.Odb.OID)parent.GetId();
}
else
{
parentOid = null;
}
}
public static void ValidateNode(NeoDatis.Btree.IBTreeNode node, bool isRoot)
{
if (!on)
{
return;
}
ValidateNode(node);
if (isRoot && node.HasParent())
{
throw new NeoDatis.Btree.Exception.BTreeNodeValidationException("Root node with a parent: "
+ node.ToString());
}
if (!isRoot && !node.HasParent())
{
throw new NeoDatis.Btree.Exception.BTreeNodeValidationException("Internal node without parent: "
+ node.ToString());
}
}
private static void CheckValuesOfChild(NeoDatis.Btree.IKeyAndValue key, NeoDatis.Btree.IBTreeNode
node)
{
if (!on)
{
return;
}
if (node == null)
{
return;
}
for (int i = 0; i < node.GetNbKeys(); i++)
{
if (node.GetKeyAndValueAt(i).GetKey().CompareTo(key.GetKey()) >= 0)
{
throw new NeoDatis.Btree.Exception.BTreeNodeValidationException("Left child with values bigger than pivot "
+ key + " : " + node.ToString());
}
}
}
public static void CheckDuplicateChildren(NeoDatis.Btree.IBTreeNode node1, NeoDatis.Btree.IBTreeNode
node2)
{
if (!on)
{
return;
}
for (int i = 0; i < node1.GetNbChildren(); i++)
{
NeoDatis.Btree.IBTreeNode child1 = node1.GetChildAt(i, true);
for (int j = 0; j < node2.GetNbChildren(); j++)
{
if (child1 == node2.GetChildAt(j, true))
{
throw new NeoDatis.Btree.Exception.BTreeNodeValidationException("Duplicated node : "
+ child1);
}
}
}
}
public override object GetValueAt(NeoDatis.Btree.IBTreeNode node, int currentIndex
)
{
if (currentValue == null)
{
currentValue = (System.Collections.IList)node.GetValueAsObjectAt(currentIndex);
}
int listSize = currentValue.Count;
if (listSize > currenListIndex)
{
object value = currentValue[currenListIndex];
currenListIndex++;
return(value);
}
// We have reached the end of the list or the list is empty
// We must continue iterate in the current node / btree
currenListIndex = 0;
currentValue = null;
return(null);
}
public virtual NeoDatis.Btree.IKeyAndValue GetSmallest(NeoDatis.Btree.IBTreeNode
node, bool delete)
{
if (!node.IsLeaf())
{
NeoDatis.Btree.IBTreeNode child = node.GetChildAt(0, true);
if (child.GetNbKeys() == degree - 1)
{
node = PrepareForDelete(node, child, 0);
}
child = node.GetChildAt(0, true);
return(GetSmallest(child, delete));
}
NeoDatis.Btree.IKeyAndValue kav = node.GetKeyAndValueAt(0);
if (delete)
{
node.DeleteKeyAndValueAt(0, true);
persister.SaveNode(node);
}
return(kav);
}
/// <summary>Loads a node from its id.</summary>
/// <remarks>
/// Loads a node from its id. Tries to get if from memory, if not present
/// then loads it from odb storage
/// </remarks>
/// <param name="id">The id of the nod</param>
/// <returns>The node with the specific id</returns>
public virtual NeoDatis.Btree.IBTreeNode LoadNodeById(object id)
{
NeoDatis.Odb.OID oid = (NeoDatis.Odb.OID)id;
// Check if node is in memory
NeoDatis.Btree.IBTreeNode node = (NeoDatis.Btree.IBTreeNode)oids[oid];
if (node != null)
{
nbLoadNodesFromCache++;
return(node);
}
nbLoadNodes++;
// else load from odb
try
{
if (NeoDatis.Odb.OdbConfiguration.IsDebugEnabled(LogId))
{
NeoDatis.Tool.DLogger.Debug("Loading node with id " + oid);
}
if (oid == null)
{
throw new NeoDatis.Odb.ODBRuntimeException(NeoDatis.Btree.BTreeError.InvalidIdForBtree
.AddParameter(oid));
}
NeoDatis.Btree.IBTreeNode pn = (NeoDatis.Btree.IBTreeNode)engine.GetObjectFromOid
(oid);
pn.SetId(oid);
if (tree != null)
{
pn.SetBTree(tree);
}
// Keep the node in memory
oids.Add(oid, pn);
return(pn);
}
catch (System.Exception e)
{
throw new NeoDatis.Odb.ODBRuntimeException(NeoDatis.Btree.BTreeError.InternalError
, e);
}
}
/// <summary>
/// saves the bree node Only puts the current node in an 'modified Node' map
/// to be saved on commit
/// </summary>
public virtual object SaveNode(NeoDatis.Btree.IBTreeNode node)
{
NeoDatis.Odb.OID oid = null;
// Here we only save the node if it does not have id,
// else we just save into the hashmap
if (node.GetId() == NeoDatis.Odb.Impl.Core.Layers.Layer3.Engine.StorageEngineConstant
.NullObjectId)
{
try
{
nbSaveNodes++;
// first get the oid. : -2:it could be any value
oid = engine.GetObjectWriter().GetIdManager().GetNextObjectId(-2);
node.SetId(oid);
oid = engine.Store(oid, node);
if (NeoDatis.Odb.OdbConfiguration.IsDebugEnabled(LogId))
{
NeoDatis.Tool.DLogger.Debug("Saved node id " + oid);
}
// + " : " +
// node.toString());
if (tree != null && node.GetBTree() == null)
{
node.SetBTree(tree);
}
oids.Add(oid, node);
return(oid);
}
catch (System.Exception e)
{
throw new NeoDatis.Odb.ODBRuntimeException(NeoDatis.Btree.BTreeError.InternalError
.AddParameter("While saving node"), e);
}
}
nbSaveNodesInCache++;
oid = (NeoDatis.Odb.OID)node.GetId();
oids.Add(oid, node);
AddModifiedOid(oid);
return(oid);
}
/// <summary>
/// Can only merge node without intersection => the greater key of this must
/// be smaller than the smallest key of the node
/// </summary>
public virtual void MergeWith(NeoDatis.Btree.IBTreeNode node)
{
NeoDatis.Btree.Tool.BTreeValidator.ValidateNode(this);
NeoDatis.Btree.Tool.BTreeValidator.ValidateNode(node);
CheckIfCanMergeWith(node);
int j = nbKeys;
for (int i = 0; i < node.GetNbKeys(); i++)
{
SetKeyAndValueAt(node.GetKeyAt(i), node.GetValueAsObjectAt(i), j, false, false);
SetChildAt(node, i, j, false);
j++;
}
// in this, we have to take the last child
if (node.GetNbChildren() > node.GetNbKeys())
{
SetChildAt(node, node.GetNbChildren() - 1, j, true);
}
nbKeys += node.GetNbKeys();
nbChildren += node.GetNbChildren();
NeoDatis.Btree.Tool.BTreeValidator.ValidateNode(this);
}
public override void SetParent(NeoDatis.Btree.IBTreeNode node)
{
parent = node;
}
public override void Clear()
{
base.Clear();
parent = null;
parentOid = null;
childrenOids = null;
oid = null;
}
protected override void Init()
{
childrenOids = new NeoDatis.Odb.OID[maxNbChildren];
parentOid = null;
parent = null;
}
