org.apache.lucene.facet.sortedset

Class SortedSetDocValuesReaderState

java.lang.Object

org.apache.lucene.facet.sortedset.SortedSetDocValuesReaderState

Direct Known Subclasses:

DefaultSortedSetDocValuesReaderState

public abstract class SortedSetDocValuesReaderState
extends Object

Wraps a IndexReader and resolves ords using existing SortedSetDocValues APIs without a separate taxonomy index. This only supports flat facets (dimension + label), and it makes faceting a bit slower, adds some cost at reopen time, but avoids managing the separate taxonomy index. It also requires less RAM than the taxonomy index, as it manages the flat (2-level) hierarchy more efficiently. In addition, the tie-break during faceting is now meaningful (in label sorted order).

NOTE: creating an instance of this class is somewhat costly, as it computes per-segment ordinal maps, so you should create it once and re-use that one instance for a given IndexReader.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	SortedSetDocValuesReaderState.OrdRange Holds start/end range of ords, which maps to one dimension (someday we may generalize it to map to hierarchies within one dimension).

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SortedSetDocValuesReaderState() Sole constructor.

Method Summary

Methods

Modifier and Type	Method and Description
abstract SortedSetDocValues	getDocValues() Return top-level doc values.
abstract String	getField() Indexed field we are reading.
abstract SortedSetDocValuesReaderState.OrdRange	getOrdRange(String dim) Returns the SortedSetDocValuesReaderState.OrdRange for this dimension.
abstract IndexReader	getOrigReader() Returns top-level index reader.
abstract Map<String,SortedSetDocValuesReaderState.OrdRange>	getPrefixToOrdRange() Returns mapping from prefix to SortedSetDocValuesReaderState.OrdRange.
abstract int	getSize() Number of unique labels.

Methods inherited from class java.lang.Object

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

Constructor Detail

SortedSetDocValuesReaderState

protected SortedSetDocValuesReaderState()

Sole constructor.

Method Detail

getDocValues

public abstract SortedSetDocValues getDocValues()
                                         throws IOException

Return top-level doc values.

Throws:

IOException

getField

public abstract String getField()

Indexed field we are reading.

getOrdRange

public abstract SortedSetDocValuesReaderState.OrdRange getOrdRange(String dim)

Returns the SortedSetDocValuesReaderState.OrdRange for this dimension.

getPrefixToOrdRange

public abstract Map<String,SortedSetDocValuesReaderState.OrdRange> getPrefixToOrdRange()

Returns mapping from prefix to SortedSetDocValuesReaderState.OrdRange.

getOrigReader

public abstract IndexReader getOrigReader()

Returns top-level index reader.

getSize

public abstract int getSize()

Number of unique labels.