org.apache.lucene.index

Class ParallelLeafReader

java.lang.Object

org.apache.lucene.index.IndexReader

org.apache.lucene.index.LeafReader

org.apache.lucene.index.ParallelLeafReader

All Implemented Interfaces:

Closeable, AutoCloseable

public class ParallelLeafReader
extends LeafReader

An LeafReader which reads multiple, parallel indexes. Each index added must have the same number of documents, but typically each contains different fields. Deletions are taken from the first reader. Each document contains the union of the fields of all documents with the same document number. When searching, matches for a query term are from the first index added that has the field.

This is useful, e.g., with collections that have large fields which change rarely and small fields that change more frequently. The smaller fields may be re-indexed in a new index and both indexes may be searched together.

Warning: It is up to you to make sure all indexes are created and modified the same way. For example, if you add documents to one index, you need to add the same documents in the same order to the other indexes. Failure to do so will result in undefined behavior.

Nested Class Summary

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

Constructor Summary

Constructors

Constructor and Description
ParallelLeafReader(boolean closeSubReaders, LeafReader... readers) Create a ParallelLeafReader based on the provided readers.
ParallelLeafReader(boolean closeSubReaders, LeafReader[] readers, LeafReader[] storedFieldsReaders) Expert: create a ParallelLeafReader based on the provided readers and storedFieldReaders; when a document is loaded, only storedFieldsReaders will be used.
ParallelLeafReader(LeafReader... readers) Create a ParallelLeafReader based on the provided readers; auto-closes the given readers on IndexReader.close().

Method Summary

Modifier and Type	Method and Description
void	addCoreClosedListener(LeafReader.CoreClosedListener listener) Expert: adds a CoreClosedListener to this reader's shared core
void	checkIntegrity() Checks consistency of this reader.
protected void	doClose() Implements close.
void	document(int docID, StoredFieldVisitor visitor) Expert: visits the fields of a stored document, for custom processing/loading of each field.
Fields	fields() Returns Fields for this reader.
BinaryDocValues	getBinaryDocValues(String field) Returns BinaryDocValues for this field, or null if no BinaryDocValues were indexed for this field.
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.
Bits	getLiveDocs() Returns the Bits representing live (not deleted) docs.
NumericDocValues	getNormValues(String field) Returns NumericDocValues representing norms for this field, or null if no NumericDocValues were indexed.
NumericDocValues	getNumericDocValues(String field) Returns NumericDocValues for this field, or null if no NumericDocValues were indexed for this field.
LeafReader[]	getParallelReaders() Returns the LeafReaders that were passed on init.
PointValues	getPointValues() Returns the PointValues used for numeric or spatial searches, or null if there are no point fields.
SortedDocValues	getSortedDocValues(String field) Returns SortedDocValues for this field, or null if no SortedDocValues were indexed for this field.
SortedNumericDocValues	getSortedNumericDocValues(String field) Returns SortedNumericDocValues for this field, or null if no SortedNumericDocValues were indexed for this field.
SortedSetDocValues	getSortedSetDocValues(String field) Returns SortedSetDocValues for this field, or null if no SortedSetDocValues were indexed for this field.
Fields	getTermVectors(int docID) Retrieve term vectors for this document, or null if term vectors were not indexed.
int	maxDoc() Returns one greater than the largest possible document number.
int	numDocs() Returns the number of documents in this index.
void	removeCoreClosedListener(LeafReader.CoreClosedListener listener) Expert: removes a CoreClosedListener from this reader's shared core
String	toString()

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

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

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

addReaderClosedListener, close, decRef, document, document, ensureOpen, equals, getCombinedCoreAndDeletesKey, getCoreCacheKey, 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

ParallelLeafReader

public ParallelLeafReader(LeafReader... readers)
                   throws IOException

Create a ParallelLeafReader based on the provided readers; auto-closes the given readers on IndexReader.close().

Throws:

IOException

ParallelLeafReader

public ParallelLeafReader(boolean closeSubReaders,
                          LeafReader... readers)
                   throws IOException

Create a ParallelLeafReader based on the provided readers.

Throws:

IOException

ParallelLeafReader

public ParallelLeafReader(boolean closeSubReaders,
                          LeafReader[] readers,
                          LeafReader[] storedFieldsReaders)
                   throws IOException

Expert: create a ParallelLeafReader based on the provided readers and storedFieldReaders; when a document is loaded, only storedFieldsReaders will be used.

Throws:

IOException

Method Detail

toString

public String toString()

Overrides:

toString in class Object

addCoreClosedListener

public void addCoreClosedListener(LeafReader.CoreClosedListener listener)

Description copied from class: LeafReader

Expert: adds a CoreClosedListener to this reader's shared core

Specified by:

addCoreClosedListener in class LeafReader

removeCoreClosedListener

public void removeCoreClosedListener(LeafReader.CoreClosedListener listener)

Description copied from class: LeafReader

Expert: removes a CoreClosedListener from this reader's shared core

Specified by:

removeCoreClosedListener in class LeafReader

getFieldInfos

public FieldInfos getFieldInfos()

Get the FieldInfos describing all fields in this reader.

NOTE: the returned field numbers will likely not correspond to the actual field numbers in the underlying readers, and codec metadata (FieldInfo.getAttribute(String) will be unavailable.

Specified by:

getFieldInfos in class LeafReader

getLiveDocs

public Bits getLiveDocs()

Description copied from class: LeafReader

Returns the Bits representing live (not deleted) docs. A set bit indicates the doc ID has not been deleted. If this method returns null it means there are no deleted documents (all documents are live). The returned instance has been safely published for use by multiple threads without additional synchronization.

Specified by:

getLiveDocs in class LeafReader

fields

public Fields fields()

Description copied from class: LeafReader

Returns Fields for this reader. This method will not return null.

Specified by:

fields in class LeafReader

numDocs

public int numDocs()

Description copied from class: IndexReader

Returns the number of documents in this index.

Specified by:

numDocs in class IndexReader

maxDoc

public int maxDoc()

Description copied from class: IndexReader

Returns one greater than the largest possible document number. This may be used to, e.g., determine how big to allocate an array which will have an element for every document number in an index.

Specified by:

maxDoc in class IndexReader

document

public void document(int docID,
                     StoredFieldVisitor visitor)
              throws IOException

Description copied from class: IndexReader

Expert: visits the fields of a stored document, for custom processing/loading of each field. If you simply want to load all fields, use IndexReader.document(int). If you want to load a subset, use DocumentStoredFieldVisitor.

Specified by:

document in class IndexReader

Throws:

IOException

getTermVectors

public Fields getTermVectors(int docID)
                      throws IOException

Description copied from class: IndexReader

Retrieve term vectors for this document, or null if term vectors were not indexed. The returned Fields instance acts like a single-document inverted index (the docID will be 0).

Specified by:

getTermVectors in class IndexReader

Throws:

IOException

doClose

protected void doClose()
                throws IOException

Description copied from class: IndexReader

Implements close.

Specified by:

doClose in class IndexReader

Throws:

IOException

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.

Specified by:

getNumericDocValues in class LeafReader

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.

Specified by:

getBinaryDocValues in class LeafReader

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.

Specified by:

getSortedDocValues in class LeafReader

Throws:

IOException

getSortedNumericDocValues

public SortedNumericDocValues getSortedNumericDocValues(String field)
                                                 throws IOException

Description copied from class: LeafReader

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

Specified by:

getSortedNumericDocValues in class LeafReader

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.

Specified by:

getSortedSetDocValues in class LeafReader

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

Specified by:

getDocsWithField in class LeafReader

Throws:

IOException

getNormValues

public NumericDocValues getNormValues(String field)
                               throws IOException

Description copied from class: LeafReader

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

Specified by:

getNormValues in class LeafReader

Throws:

IOException

getPointValues

public PointValues getPointValues()

Description copied from class: LeafReader

Returns the PointValues used for numeric or spatial searches, or null if there are no point fields.

Specified by:

getPointValues in class LeafReader

checkIntegrity

public void checkIntegrity()
                    throws IOException

Description copied from class: LeafReader

Checks consistency of this reader.

Note that this may be costly in terms of I/O, e.g. may involve computing a checksum value against large data files.

Specified by:

checkIntegrity in class LeafReader

Throws:

IOException

getParallelReaders

public LeafReader[] getParallelReaders()

Returns the LeafReaders that were passed on init.