Package org.h2.index

Class IndexCursor

java.lang.Object

org.h2.index.IndexCursor

All Implemented Interfaces:

Cursor

public class IndexCursor
extends java.lang.Object
implements Cursor

The filter used to walk through an index. This class supports IN(..) and IN(SELECT ...) optimizations.

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	alwaysFalse
private Cursor	cursor
private SearchRow	end
private Column	inColumn
private Index	index
private IndexColumn[]	indexColumns
private Value[]	inList
private int	inListIndex
private ResultInterface	inResult
private SearchRow	intersects
private SessionLocal	session
private SearchRow	start
private Table	table

Constructor Summary

Constructors

Constructor	Description
IndexCursor()

Method Summary

Modifier and Type	Method	Description
private boolean	canUseIndexFor(Column column)
private boolean	canUseIndexForIn(Column column)
void	find(SessionLocal s, java.util.ArrayList<IndexCondition> indexConditions)	Re-evaluate the start and end values of the index search for rows.
private void	find(Value v)
Row	get()	Get the complete current row.
SearchRow	getEnd()	Get end search row.
private Value	getMax(Value a, Value b, boolean bigger)
SearchRow	getSearchRow()	Get the current row.
private SearchRow	getSearchRow(SearchRow row, int columnId, Value v, boolean max)
private SearchRow	getSpatialSearchRow(SearchRow row, int columnId, Value v)
SearchRow	getStart()	Get start search row.
boolean	isAlwaysFalse()	Check if the result is empty for sure.
boolean	next()	Skip to the next row if one is available.
private void	nextCursor()
void	prepare(SessionLocal s, java.util.ArrayList<IndexCondition> indexConditions)	Prepare this index cursor to make a lookup in index.
boolean	previous()	Skip to the previous row if one is available.
void	setIndex(Index index)

Methods inherited from class java.lang.Object

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

Field Detail

session

private SessionLocal session

index

private Index index

table

private Table table

indexColumns

private IndexColumn[] indexColumns

alwaysFalse

private boolean alwaysFalse

start

private SearchRow start

end

private SearchRow end

intersects

private SearchRow intersects

cursor

private Cursor cursor

inColumn

private Column inColumn

inListIndex

private int inListIndex

inList

private Value[] inList

inResult

private ResultInterface inResult

Constructor Detail

IndexCursor

public IndexCursor()

Method Detail

setIndex

public void setIndex(Index index)

prepare

public void prepare(SessionLocal s,
                    java.util.ArrayList<IndexCondition> indexConditions)

Prepare this index cursor to make a lookup in index.

Parameters:

s - Session.

indexConditions - Index conditions.

find

public void find(SessionLocal s,
                 java.util.ArrayList<IndexCondition> indexConditions)

Re-evaluate the start and end values of the index search for rows.

Parameters:

s - the session

indexConditions - the index conditions

canUseIndexForIn

private boolean canUseIndexForIn(Column column)

canUseIndexFor

private boolean canUseIndexFor(Column column)

getSpatialSearchRow

private SearchRow getSpatialSearchRow(SearchRow row,
                                      int columnId,
                                      Value v)

getSearchRow

private SearchRow getSearchRow(SearchRow row,
                               int columnId,
                               Value v,
                               boolean max)

getMax

private Value getMax(Value a,
                     Value b,
                     boolean bigger)

isAlwaysFalse

public boolean isAlwaysFalse()

Check if the result is empty for sure.

Returns:

true if it is

getStart

public SearchRow getStart()

Get start search row.

Returns:

search row

getEnd

public SearchRow getEnd()

Get end search row.

Returns:

search row

get

public Row get()

Description copied from interface: Cursor

Get the complete current row. All column are available.

Specified by:

get in interface Cursor

Returns:

the complete row

getSearchRow

public SearchRow getSearchRow()

Description copied from interface: Cursor

Get the current row. Only the data for indexed columns is available in this row.

Specified by:

getSearchRow in interface Cursor

Returns:

the search row

next

public boolean next()

Description copied from interface: Cursor

Skip to the next row if one is available.

Specified by:

next in interface Cursor

Returns:

true if another row is available

nextCursor

private void nextCursor()

find

private void find(Value v)

previous

public boolean previous()

Description copied from interface: Cursor

Skip to the previous row if one is available. No filtering is made here.

Specified by:

previous in interface Cursor

Returns:

true if another row is available