public BTreeNode(Transaction trans, Db4objects.Db4o.Internal.Btree.BTreeNode firstChild
, Db4objects.Db4o.Internal.Btree.BTreeNode secondChild) : this(firstChild._btree
, 2, false, 0, 0, 0)
{
_keys[0] = firstChild._keys[0];
_children[0] = firstChild;
_keys[1] = secondChild._keys[0];
_children[1] = secondChild;
Write(trans.SystemTransaction());
firstChild.SetParentID(trans, GetID());
secondChild.SetParentID(trans, GetID());
}
public BTree(Transaction trans, BTreeConfiguration config, int id, IIndexable4 keyHandler
, int treeNodeSize) : base(config._idSystem)
{
_config = config;
if (null == keyHandler)
{
throw new ArgumentNullException();
}
_nodeSize = treeNodeSize;
_nodeCache = CacheFactory.NewLRUIntCache(config._cacheSize);
_halfNodeSize = _nodeSize / 2;
_nodeSize = _halfNodeSize * 2;
_keyHandler = keyHandler;
SetID(id);
if (IsNew())
{
SetStateDirty();
_root = new BTreeNode(this, 0, true, 0, 0, 0);
_root.Write(trans.SystemTransaction());
AddNode(_root);
Write(trans.SystemTransaction());
}
else
{
SetStateDeactivated();
}
}
private void EnsureActive(Transaction trans)
{
if (!IsActive())
{
Read(trans.SystemTransaction());
}
}
private void FinishTransaction(Transaction trans)
{
Transaction systemTransaction = trans.SystemTransaction();
WriteAllNodes(systemTransaction);
Write(systemTransaction);
Purge();
}
public virtual void Add(Transaction trans, IPreparedComparison preparedComparison
, object key)
{
EnsureActive(trans);
Enlist(trans);
BTreeNode rootOrSplit = _root.Add(trans, preparedComparison, key);
if (rootOrSplit != null && rootOrSplit != _root)
{
EnsureDirty(trans);
_root = new BTreeNode(trans, _root, rootOrSplit);
_root.Write(trans.SystemTransaction());
AddNode(_root);
}
ConvertCacheEvictedNodesToReadMode();
}
internal void PrepareWrite(Transaction trans)
{
if (_dead)
{
return;
}
BTreeNodeCacheEntry cacheEntry = Btree().CacheEntry(this);
if (CanWrite())
{
return;
}
ByteArrayBuffer buffer = cacheEntry.Buffer();
if (buffer != null)
{
buffer.Seek(0);
Read(trans.SystemTransaction(), buffer);
cacheEntry.Buffer(null);
}
else
{
Read(trans.SystemTransaction());
}
_btree.AddToProcessing(this);
}
internal ByteArrayBuffer PrepareRead(Transaction trans)
{
BTreeNodeCacheEntry cacheEntry = Btree().CacheEntry(this);
if (CanWrite())
{
return null;
}
if (IsNew())
{
return null;
}
Transaction systemTransaction = trans.SystemTransaction();
ByteArrayBuffer buffer = cacheEntry.Buffer();
if (buffer != null)
{
// Cache hit, still unread
buffer.Seek(0);
Read(systemTransaction, buffer);
cacheEntry.Buffer(null);
_btree.AddToProcessing(this);
return null;
}
buffer = ProduceReadBuffer(systemTransaction);
ReadNodeHeader(buffer);
cacheEntry.Buffer(buffer);
return buffer;
}
private Db4objects.Db4o.Internal.Btree.BTreeNode Split(Transaction trans)
{
Db4objects.Db4o.Internal.Btree.BTreeNode res = new Db4objects.Db4o.Internal.Btree.BTreeNode
(_btree, _btree._halfNodeSize, _isLeaf, _parentID, GetID(), _nextID);
System.Array.Copy(_keys, _btree._halfNodeSize, res._keys, 0, _btree._halfNodeSize
);
for (int i = _btree._halfNodeSize; i < _keys.Length; i++)
{
_keys[i] = null;
}
if (_children != null)
{
res._children = new object[_btree.NodeSize()];
System.Array.Copy(_children, _btree._halfNodeSize, res._children, 0, _btree._halfNodeSize
);
for (int i = _btree._halfNodeSize; i < _children.Length; i++)
{
_children[i] = null;
}
}
_count = _btree._halfNodeSize;
res.Write(trans.SystemTransaction());
_btree.AddNode(res);
int splitID = res.GetID();
PointNextTo(trans, splitID);
SetNextID(trans, splitID);
if (_children != null)
{
for (int i = 0; i < _btree._halfNodeSize; i++)
{
if (res._children[i] == null)
{
break;
}
res.Child(i).SetParentID(trans, splitID);
}
}
_btree.NotifySplit(trans, this, res);
return res;
}
// do nothing.
public override BTree GetIndex(Transaction trans)
{
return(((LocalTransaction)trans.SystemTransaction()).CommitTimestampSupport().TimestampToId
());
}
// do nothing.
public override BTree GetIndex(Transaction trans)
{
return ((LocalTransaction)trans.SystemTransaction()).CommitTimestampSupport().TimestampToId
();
}
