mondrian.rolap.agg

Class SegmentWithData

java.lang.Object

mondrian.rolap.agg.Segment

mondrian.rolap.agg.SegmentWithData

public class SegmentWithData
extends Segment

Extension to Segment with a data set.

Author:

jhyde

Nested Class Summary

Nested classes/interfaces inherited from class mondrian.rolap.agg.Segment

Segment.ExcludedRegion

Field Summary

Fields

Modifier and Type	Field and Description
(package private) SegmentAxis[]	axes An array of axes, one for each constraining column, containing the values returned for that constraining column.

Fields inherited from class mondrian.rolap.agg.Segment

columns, compoundPredicateList, constrainedColumnsBitKey, excludedRegions, id, measure, predicates, star

Constructor Summary

Constructors

Constructor and Description
SegmentWithData(Segment segment, SegmentDataset data, SegmentAxis[] axes) Creates a SegmentWithData from an existing Segment.

Method Summary

Modifier and Type	Method and Description
(package private) SegmentWithData	createSubSegment(BitSet[] axisKeepBitSets, int bestColumn, StarColumnPredicate bestPredicate, List<Segment.ExcludedRegion> excludedRegions) Creates a Segment which has the same dimensionality as this Segment and a subset of the values.
protected void	describeAxes(StringBuilder buf, int i, boolean values)
int	getCellCount() Returns the number of cells in this Segment, deducting cells in excluded regions.
Object	getCellValue(Object[] keys) Retrieves the value at the location identified by keys.
SegmentDataset	getData() Returns the data set.
(package private) boolean	wouldContain(Object[] keys) Returns whether the given set of key values will be in this segment when it finishes loading.

Methods inherited from class mondrian.rolap.agg.Segment

createDataset, getColumns, getCompoundPredicateList, getConstrainedColumnsBitKey, getExcludedRegions, getHeader, getStar, isExcluded, matches, print, toString

Methods inherited from class java.lang.Object

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

Field Detail

axes

final SegmentAxis[] axes

An array of axes, one for each constraining column, containing the values returned for that constraining column.

Constructor Detail

SegmentWithData

public SegmentWithData(Segment segment,
                       SegmentDataset data,
                       SegmentAxis[] axes)

Creates a SegmentWithData from an existing Segment.

Parameters:

segment - Segment (without data)

data - Data set

Method Detail

describeAxes

protected void describeAxes(StringBuilder buf,
                            int i,
                            boolean values)

Overrides:

describeAxes in class Segment

getCellValue

public Object getCellValue(Object[] keys)

Retrieves the value at the location identified by keys.

Returns

• Util.nullValue if the cell value is null (because no fact table rows met those criteria);
• null if the value is not supposed to be in this segment (because one or more of the keys do not pass the axis criteria);
• the data value otherwise

See Also:

make package-private?

wouldContain

boolean wouldContain(Object[] keys)

Returns whether the given set of key values will be in this segment when it finishes loading.

getCellCount

public int getCellCount()

Returns the number of cells in this Segment, deducting cells in excluded regions.

This method may return a value which is slightly too low, or occasionally even negative. This occurs when a Segment has more than one excluded region, and those regions overlap. Cells which are in both regions will be counted twice.

Returns:

Number of cells in this Segment

createSubSegment

SegmentWithData createSubSegment(BitSet[] axisKeepBitSets,
                                 int bestColumn,
                                 StarColumnPredicate bestPredicate,
                                 List<Segment.ExcludedRegion> excludedRegions)

Creates a Segment which has the same dimensionality as this Segment and a subset of the values.

If bestColumn is not -1, the bestColumnth column's predicate should be replaced by bestPredicate.

Parameters:

axisKeepBitSets - For each axis, a bitmap of the axis values to keep; each axis must have at least one bit set

bestColumn - The column that retains most of its values

bestPredicate -

excludedRegions - List of regions to exclude from segment

Returns:

Segment containing a subset of the values

getData

public final SegmentDataset getData()

Returns the data set.

WARNING: the returned SegmentDataset reference should not be modified; it is assumed to be invariant.

Returns:

The data reference