com.bigdata.btree

Interface ISimpleTreeIndexAccess

All Superinterfaces:

ISimpleIndexAccess

All Known Implementing Classes:

AbstractBTree, AbstractHTree, BTree, CommitRecordIndex, CommitTimeIndex, CounterSetBTree, EventReceiver.EventBTree, HTree, IndexSegment, IndexSegmentIndex, JournalIndex, MetadataIndex, Name2Addr, TestMROWTransactions.MyBTree, TestRestartSafe.MyBTree, TxId2CommitTimeIndex

public interface ISimpleTreeIndexAccess
extends ISimpleIndexAccess

Extended interface for tree-structured indices.

Author:

Bryan Thompson

Method Summary

Methods

Modifier and Type	Method and Description
long	getEntryCount() The #of tuples in the tree.
int	getHeight() The height of the tree.
long	getLeafCount() The #of leaf nodes in the tree.
long	getNodeCount() The #of non-leaf nodes in the tree.
boolean	isBalanced() Return true iff the tree is balanced.

Methods inherited from interface com.bigdata.btree.ISimpleIndexAccess

getStore, rangeCount, removeAll, scan

Method Detail

getNodeCount

long getNodeCount()

The #of non-leaf nodes in the tree.

getLeafCount

long getLeafCount()

The #of leaf nodes in the tree.

getEntryCount

long getEntryCount()

The #of tuples in the tree.

isBalanced

boolean isBalanced()

Return true iff the tree is balanced.

Note: Not all tree-structured indices are balanced. For example, the BTree is balanced, but the HTree is not balanced. The height of an unbalanced tree must be discovered through a traversal of the tree.

getHeight

int getHeight()

The height of the tree. The height is the #of levels minus one. A tree with only a root leaf has height := 0. A tree with a root node and one level of leaves under it has height := 1.

Note that all leaves of a balanced tree (such as a B+Tree) are at the same height (this is what is means to be "balanced"). Also note that the height only changes when we split or join the root node (a B+Tree maintains balance by growing and shrinking in levels from the top rather than the leaves).

Throws:

UnsupportedOperationException - if the tree is not a balanced tree.

See Also:

isBalanced()