com.bigdata.btree.data
Interface INodeData

All Superinterfaces:

IAbstractNodeData, IDataRecordAccess

All Known Implementing Classes:

IndexSegment.ImmutableNodeFactory.ImmutableNode, IndexSegmentBuilder.SimpleNodeData, MutableNodeData, Node

public interface INodeData
extends IAbstractNodeData

Interface for low-level data access for the non-leaf nodes of a B+-Tree.

Version:

$Id: INodeData.java 2265 2009-10-26 12:51:06Z thompsonbry $

Author:

Bryan Thompson

Method Summary

long	getChildAddr(int index) Return the persistent addresses of the specified child node.
int	getChildCount() The #of children of this node.
int	getChildEntryCount(int index) Return the #of tuples spanned by the indicated child of this node.

Methods inherited from interface com.bigdata.btree.data.IAbstractNodeData

data, getKeyCount, getKeys, getMaximumVersionTimestamp, getMinimumVersionTimestamp, getSpannedTupleCount, hasVersionTimestamps, isCoded, isLeaf, isReadOnly

Method Detail

getChildCount

int getChildCount()

The #of children of this node. Either all children will be nodes or all children will be leaves. The #of children of a node MUST be IAbstractNodeData.getKeyCount()+1

Returns:

The #of children of this node.

getChildAddr

long getChildAddr(int index)

Return the persistent addresses of the specified child node.

Parameters:

index - The index of the child in [0:nkeys].

Returns:

The persistent child address -or- zero(0L) if the child is not persistent.

getChildEntryCount

int getChildEntryCount(int index)

Return the #of tuples spanned by the indicated child of this node. The sum of the values returned by this method across the children of the node should always equal the value returned by IAbstractNodeData.getSpannedTupleCount() . These data are used to support fast computation of the index at which a key occurs and the #of entries in a given key range.

Parameters:

index - The index of the child in [0:nkeys].

Returns:

The #of tuples spanned by that child.