com.bigdata.btree

Class BaseIndexStats

java.lang.Object

com.bigdata.btree.BaseIndexStats

Direct Known Subclasses:

PageStats

public class BaseIndexStats
extends Object

Basic stats that are available for all index types and whose collection does not require visitation of the index pages.

Author:

Bryan Thompson

Field Summary

Fields

Modifier and Type	Field and Description
int	height The height (aka depth) of the index
IndexTypeEnum	indexType The type of index.
int	m The current branching factor for the index.
String	name The name associated with the index -or- null if the index is not named.
long	nleaves The #of leaves visited.
long	nnodes The #of nodes visited.
long	ntuples The #of entries in the index.

Constructor Summary

Constructors

Constructor and Description
BaseIndexStats() Zero-arg constructor does NOT initialize the fields.
BaseIndexStats(ICheckpointProtocol ndx) Initializes the fields for the specified index.

Method Summary

Methods

Modifier and Type	Method and Description
String	getDataRow() Return a row of data for an index as aggregated by this PageStats object.
String	getHeaderRow() Return the header row for a table.
static void	writeOn(PrintWriter out, Map<String,BaseIndexStats> statsMap) Helper method may be used to write out a tab-delimited table of the statistics.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

indexType

public IndexTypeEnum indexType

The type of index.

name

public String name

The name associated with the index -or- null if the index is not named.

m

public int m

The current branching factor for the index. TODO GIST: [m] is BTree specific. The [addressBits] concept is the parallel for the HTree. This field should probably be moved into the concrete instances of the PageStats class.

ntuples

public long ntuples

The #of entries in the index.

height

public int height

The height (aka depth) of the index

nnodes

public long nnodes

The #of nodes visited.

nleaves

public long nleaves

The #of leaves visited.

Constructor Detail

BaseIndexStats

public BaseIndexStats()

Zero-arg constructor does NOT initialize the fields.

BaseIndexStats

public BaseIndexStats(ICheckpointProtocol ndx)

Initializes the fields for the specified index.

Method Detail

getHeaderRow

public String getHeaderRow()

Return the header row for a table.

Returns:

The header row.

getDataRow

public String getDataRow()

Return a row of data for an index as aggregated by this PageStats object.

See Also:

getHeaderRow()

writeOn

public static void writeOn(PrintWriter out,
           Map<String,BaseIndexStats> statsMap)

Helper method may be used to write out a tab-delimited table of the statistics.

Parameters:

out - Where to write the statistics.