org.apache.lucene.uninverting

Class UninvertingReader

java.lang.Object

org.apache.lucene.index.IndexReader

org.apache.lucene.index.LeafReader

org.apache.lucene.index.FilterLeafReader

org.apache.lucene.uninverting.UninvertingReader

All Implemented Interfaces:

Closeable, AutoCloseable

public class UninvertingReader
extends FilterLeafReader

A FilterReader that exposes indexed values as if they also had docvalues.

This is accomplished by "inverting the inverted index" or "uninversion".

The uninversion process happens lazily: upon the first request for the field's docvalues (e.g. via LeafReader.getNumericDocValues(String) or similar), it will create the docvalues on-the-fly if needed and cache it, based on the core cache key of the wrapped LeafReader.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	UninvertingReader.Type Specifies the type of uninversion to apply for the field.

Nested classes/interfaces inherited from class org.apache.lucene.index.FilterLeafReader

FilterLeafReader.FilterFields, FilterLeafReader.FilterPostingsEnum, FilterLeafReader.FilterTerms, FilterLeafReader.FilterTermsEnum

Nested classes/interfaces inherited from class org.apache.lucene.index.LeafReader

LeafReader.CoreClosedListener

Nested classes/interfaces inherited from class org.apache.lucene.index.IndexReader

IndexReader.ReaderClosedListener

Field Summary

Fields inherited from class org.apache.lucene.index.FilterLeafReader

in

Constructor Summary

Constructors

Constructor and Description
UninvertingReader(LeafReader in, Map<String,UninvertingReader.Type> mapping) Create a new UninvertingReader with the specified mapping

Method Summary

Modifier and Type	Method and Description
BinaryDocValues	getBinaryDocValues(String field) Returns BinaryDocValues for this field, or null if no BinaryDocValues were indexed for this field.
Object	getCombinedCoreAndDeletesKey() Expert: Returns a key for this IndexReader that also includes deletions, so CachingWrapperFilter can find it again.
Object	getCoreCacheKey() Expert: Returns a key for this IndexReader, so CachingWrapperFilter can find it again.
Bits	getDocsWithField(String field) Returns a Bits at the size of reader.maxDoc(), with turned on bits for each docid that does have a value for this field, or null if no DocValues were indexed for this field.
FieldInfos	getFieldInfos() Get the FieldInfos describing all fields in this reader.
NumericDocValues	getNumericDocValues(String field) Returns NumericDocValues for this field, or null if no NumericDocValues were indexed for this field.
SortedDocValues	getSortedDocValues(String field) Returns SortedDocValues for this field, or null if no SortedDocValues were indexed for this field.
SortedSetDocValues	getSortedSetDocValues(String field) Returns SortedSetDocValues for this field, or null if no SortedSetDocValues were indexed for this field.
static String[]	getUninvertedStats() Return information about the backing cache
String	toString()
static DirectoryReader	wrap(DirectoryReader in, Map<String,UninvertingReader.Type> mapping) Wraps a provided DirectoryReader.

Methods inherited from class org.apache.lucene.index.FilterLeafReader

addCoreClosedListener, checkIntegrity, doClose, document, fields, getDelegate, getLiveDocs, getNormValues, getSortedNumericDocValues, getTermVectors, maxDoc, numDocs, removeCoreClosedListener, unwrap

Methods inherited from class org.apache.lucene.index.LeafReader

addCoreClosedListenerAsReaderClosedListener, docFreq, getContext, getDocCount, getSumDocFreq, getSumTotalTermFreq, postings, postings, removeCoreClosedListenerAsReaderClosedListener, termDocsEnum, termPositionsEnum, terms, totalTermFreq

Methods inherited from class org.apache.lucene.index.IndexReader

addReaderClosedListener, close, decRef, document, document, ensureOpen, equals, getRefCount, getTermVector, hasDeletions, hashCode, incRef, leaves, numDeletedDocs, registerParentReader, removeReaderClosedListener, tryIncRef

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

UninvertingReader

public UninvertingReader(LeafReader in,
                         Map<String,UninvertingReader.Type> mapping)

Create a new UninvertingReader with the specified mapping

Expert: This should almost never be used. Use wrap(DirectoryReader, Map) instead.

Method Detail

wrap

public static DirectoryReader wrap(DirectoryReader in,
                                   Map<String,UninvertingReader.Type> mapping)
                            throws IOException

Wraps a provided DirectoryReader. Note that for convenience, the returned reader can be used normally (e.g. passed to DirectoryReader.openIfChanged(DirectoryReader)) and so on.

Throws:

IOException

getFieldInfos

public FieldInfos getFieldInfos()

Description copied from class: LeafReader

Get the FieldInfos describing all fields in this reader.

Overrides:

getFieldInfos in class FilterLeafReader

getNumericDocValues

public NumericDocValues getNumericDocValues(String field)
                                     throws IOException

Description copied from class: LeafReader

Returns NumericDocValues for this field, or null if no NumericDocValues were indexed for this field. The returned instance should only be used by a single thread.

Overrides:

getNumericDocValues in class FilterLeafReader

Throws:

IOException

getBinaryDocValues

public BinaryDocValues getBinaryDocValues(String field)
                                   throws IOException

Description copied from class: LeafReader

Returns BinaryDocValues for this field, or null if no BinaryDocValues were indexed for this field. The returned instance should only be used by a single thread.

Overrides:

getBinaryDocValues in class FilterLeafReader

Throws:

IOException

getSortedDocValues

public SortedDocValues getSortedDocValues(String field)
                                   throws IOException

Description copied from class: LeafReader

Returns SortedDocValues for this field, or null if no SortedDocValues were indexed for this field. The returned instance should only be used by a single thread.

Overrides:

getSortedDocValues in class FilterLeafReader

Throws:

IOException

getSortedSetDocValues

public SortedSetDocValues getSortedSetDocValues(String field)
                                         throws IOException

Description copied from class: LeafReader

Returns SortedSetDocValues for this field, or null if no SortedSetDocValues were indexed for this field. The returned instance should only be used by a single thread.

Overrides:

getSortedSetDocValues in class FilterLeafReader

Throws:

IOException

getDocsWithField

public Bits getDocsWithField(String field)
                      throws IOException

Description copied from class: LeafReader

Returns a Bits at the size of reader.maxDoc(), with turned on bits for each docid that does have a value for this field, or null if no DocValues were indexed for this field. The returned instance should only be used by a single thread

Overrides:

getDocsWithField in class FilterLeafReader

Throws:

IOException

getCoreCacheKey

public Object getCoreCacheKey()

Description copied from class: IndexReader

Expert: Returns a key for this IndexReader, so CachingWrapperFilter can find it again. This key must not have equals()/hashCode() methods, so "equals" means "identical".

Overrides:

getCoreCacheKey in class IndexReader

getCombinedCoreAndDeletesKey

public Object getCombinedCoreAndDeletesKey()

Description copied from class: IndexReader

Expert: Returns a key for this IndexReader that also includes deletions, so CachingWrapperFilter can find it again. This key must not have equals()/hashCode() methods, so "equals" means "identical".

Overrides:

getCombinedCoreAndDeletesKey in class IndexReader

toString

public String toString()

Overrides:

toString in class FilterLeafReader

getUninvertedStats

public static String[] getUninvertedStats()

Return information about the backing cache