Interface ColumnarFilter

All Known Implementing Classes:

DictionaryAwareColumnarFilter, IsNotNullColumnarFilter, IsNullColumnarFilter

public interface ColumnarFilter

Implementations of this interface evaluate a filter on the input Page.

FilterEvaluator will call one of filterPositionsRange or filterPositionsList depending on whether the active SelectionPositions are stored in a list or in a range.

Implementations are expected to operate on a Page containing only the required channels specified by getInputChannels.

Currently, the implementations of this interface except IS_NULL and NOT(IS_NULL), don't explicitly handle NULLs or indeterminate values, and just return FALSE for those cases. This will need to change to allow ColumnarFilter implementations to be composed in all cases (e.g. NOT filters). ColumnarFilter implementations are never composed, FilterEvaluator implementations may be composed.

Method Summary

Modifier and Type	Method	Description
int	filterPositionsList(ConnectorSession session, int[] outputPositions, int[] activePositions, int offset, int size, Page loadedPage)
int	filterPositionsRange(ConnectorSession session, int[] outputPositions, int offset, int size, Page loadedPage)
InputChannels	getInputChannels()

Method Details

filterPositionsRange

int filterPositionsRange(ConnectorSession session,
 int[] outputPositions,
 int offset,
 int size,
 Page loadedPage)

Parameters:

outputPositions - list of positions active after evaluating this filter on the input loadedPage

offset - start of input positions range evaluated by this filter

size - length of input positions range evaluated by this filter

loadedPage - input Page after using getInputChannels() to load only the required channels

Returns:

count of positions active after evaluating this filter on the input loadedPage

filterPositionsList

int filterPositionsList(ConnectorSession session,
 int[] outputPositions,
 int[] activePositions,
 int offset,
 int size,
 Page loadedPage)

Parameters:

outputPositions - list of positions active after evaluating this filter on the input loadedPage

activePositions - input positions list evaluated by this filter

offset - index in activePositions where the input positions evaluated by this filter start

size - length after offset in activePositions where the input positions evaluated by this filter end

loadedPage - input Page after using getInputChannels() to load only the required channels

Returns:

count of positions active after evaluating this filter on the input loadedPage

getInputChannels

InputChannels getInputChannels()

Returns:

InputChannels of input Page that this filter operates on