Package org.apache.lucene.spatial.prefix

Class RecursivePrefixTreeStrategy

java.lang.Object

org.apache.lucene.spatial.SpatialStrategy

org.apache.lucene.spatial.prefix.PrefixTreeStrategy

org.apache.lucene.spatial.prefix.RecursivePrefixTreeStrategy

Direct Known Subclasses:

NumberRangePrefixTreeStrategy

public class RecursivePrefixTreeStrategy
extends PrefixTreeStrategy

A PrefixTreeStrategy which uses AbstractVisitingPrefixTreeQuery. This strategy has support for searching non-point shapes (note: not tested). Even a query shape with distErrPct=0 (fully precise to the grid) should have good performance for typical data, unless there is a lot of indexed data coincident with the shape's edge.

WARNING: This API is experimental and might change in incompatible ways in the next release.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.spatial.prefix.PrefixTreeStrategy

PrefixTreeStrategy.ShapeTokenStream

Field Summary

Fields

Modifier and Type	Field	Description
protected boolean	multiOverlappingIndexedShapes
protected int	prefixGridScanLevel
protected boolean	pruneLeafyBranches

Fields inherited from class org.apache.lucene.spatial.prefix.PrefixTreeStrategy

defaultFieldValuesArrayLen, distErrPct, FIELD_TYPE, grid, pointsOnly

Fields inherited from class org.apache.lucene.spatial.SpatialStrategy

ctx

Constructor Summary

Constructors

Constructor	Description
RecursivePrefixTreeStrategy(SpatialPrefixTree grid, String fieldName)

Method Summary

Modifier and Type	Method	Description
protected Iterator<Cell>	createCellIteratorToIndex(org.locationtech.spatial4j.shape.Shape shape, int detailLevel, Iterator<Cell> reuse)
int	getPrefixGridScanLevel()
protected boolean	isGridAlignedShape(org.locationtech.spatial4j.shape.Shape shape)	A quick check of the shape to see if it is perfectly aligned to a grid.
boolean	isMultiOverlappingIndexedShapes()
boolean	isPruneLeafyBranches()
protected Query	makeGridShapeIntersectsQuery(org.locationtech.spatial4j.shape.Shape gridShape)	makeQuery(SpatialArgs) specialized for the query being a grid square.
Query	makeQuery(SpatialArgs args)	Make a Query based principally on SpatialOperation and Shape from the supplied args.
void	setMultiOverlappingIndexedShapes(boolean multiOverlappingIndexedShapes)	See ContainsPrefixTreeQuery.multiOverlappingIndexedShapes.
void	setPrefixGridScanLevel(int prefixGridScanLevel)	Sets the grid level [1-maxLevels] at which indexed terms are scanned brute-force instead of by grid decomposition.
void	setPruneLeafyBranches(boolean pruneLeafyBranches)	An optional hint affecting non-point shapes and tree cells implementing CellCanPrune, otherwise ignored.
String	toString()

Methods inherited from class org.apache.lucene.spatial.prefix.PrefixTreeStrategy

calcFacets, createIndexableFields, createIndexableFields, createIndexableFields, getDistErrPct, getGrid, isPointShape, isPointsOnly, makeDistanceValueSource, newCellToBytesRefIterator, setDefaultFieldValuesArrayLen, setDistErrPct, setPointsOnly, tokenStream

Methods inherited from class org.apache.lucene.spatial.SpatialStrategy

getFieldName, getSpatialContext, makeDistanceValueSource, makeRecipDistanceValueSource

Methods inherited from class java.lang.Object

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

Field Detail

prefixGridScanLevel

protected int prefixGridScanLevel

pruneLeafyBranches

protected boolean pruneLeafyBranches

multiOverlappingIndexedShapes

protected boolean multiOverlappingIndexedShapes

Constructor Detail

RecursivePrefixTreeStrategy

public RecursivePrefixTreeStrategy(SpatialPrefixTree grid,
                                   String fieldName)

Method Detail

getPrefixGridScanLevel

public int getPrefixGridScanLevel()

setPrefixGridScanLevel

public void setPrefixGridScanLevel(int prefixGridScanLevel)

Sets the grid level [1-maxLevels] at which indexed terms are scanned brute-force instead of by grid decomposition. By default this is maxLevels - 4. The final level, maxLevels, is always scanned.

Parameters:

prefixGridScanLevel - 1 to maxLevels

isMultiOverlappingIndexedShapes

public boolean isMultiOverlappingIndexedShapes()

setMultiOverlappingIndexedShapes

public void setMultiOverlappingIndexedShapes(boolean multiOverlappingIndexedShapes)

See ContainsPrefixTreeQuery.multiOverlappingIndexedShapes.

isPruneLeafyBranches

public boolean isPruneLeafyBranches()

setPruneLeafyBranches

public void setPruneLeafyBranches(boolean pruneLeafyBranches)

An optional hint affecting non-point shapes and tree cells implementing CellCanPrune, otherwise ignored.

It will prune away a complete set sibling leaves to their parent (recursively), resulting in ~20-50% fewer indexed cells, and consequently that much less disk and that much faster indexing. So if it's a quad tree and all 4 sub-cells are there marked as a leaf, then they will be removed (pruned) and the parent is marked as a leaf instead. This occurs recursively on up. Unfortunately, the current implementation will buffer all cells to do this, so consider disabling for high precision (low distErrPct) shapes. (default=true)

toString

public String toString()

Overrides:

toString in class SpatialStrategy

createCellIteratorToIndex

protected Iterator<Cell> createCellIteratorToIndex(org.locationtech.spatial4j.shape.Shape shape,
                                                   int detailLevel,
                                                   Iterator<Cell> reuse)

Overrides:

createCellIteratorToIndex in class PrefixTreeStrategy

makeQuery

public Query makeQuery(SpatialArgs args)

Description copied from class: SpatialStrategy

Make a Query based principally on SpatialOperation and Shape from the supplied args. It should be constant scoring of 1.

Specified by:

makeQuery in class SpatialStrategy

isGridAlignedShape

protected boolean isGridAlignedShape(org.locationtech.spatial4j.shape.Shape shape)

A quick check of the shape to see if it is perfectly aligned to a grid. Points always are as they are indivisible. It's okay to return false if the shape actually is aligned; this is an optimization hint.

makeGridShapeIntersectsQuery

protected Query makeGridShapeIntersectsQuery(org.locationtech.spatial4j.shape.Shape gridShape)

makeQuery(SpatialArgs) specialized for the query being a grid square.