org.apache.lucene.index

Class FilterAtomicReader

java.lang.Object

org.apache.lucene.index.IndexReader

org.apache.lucene.index.AtomicReader

org.apache.lucene.index.FilterAtomicReader

All Implemented Interfaces:

Closeable, AutoCloseable

public class FilterAtomicReader
extends AtomicReader

A FilterAtomicReader contains another AtomicReader, which it uses as its basic source of data, possibly transforming the data along the way or providing additional functionality. The class FilterAtomicReader itself simply implements all abstract methods of IndexReader with versions that pass all requests to the contained index reader. Subclasses of FilterAtomicReader may further override some of these methods and may also provide additional methods and fields.

NOTE: If you override getLiveDocs(), you will likely need to override numDocs() as well and vice-versa.

NOTE: If this FilterAtomicReader does not change the content the contained reader, you could consider overriding IndexReader.getCoreCacheKey() so that FieldCache and CachingWrapperFilter share the same entries for this atomic reader and the wrapped one. IndexReader.getCombinedCoreAndDeletesKey() could be overridden as well if the live docs are not changed either.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	FilterAtomicReader.FilterDocsAndPositionsEnum Base class for filtering DocsAndPositionsEnum implementations.
static class	FilterAtomicReader.FilterDocsEnum Base class for filtering DocsEnum implementations.
static class	FilterAtomicReader.FilterFields Base class for filtering Fields implementations.
static class	FilterAtomicReader.FilterTerms Base class for filtering Terms implementations.
static class	FilterAtomicReader.FilterTermsEnum Base class for filtering TermsEnum implementations.

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

AtomicReader.CoreClosedListener

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

IndexReader.ReaderClosedListener

Field Summary

Fields

Modifier and Type	Field and Description
protected AtomicReader	in The underlying AtomicReader.

Constructor Summary

Constructors

Constructor and Description
FilterAtomicReader(AtomicReader in) Construct a FilterAtomicReader based on the specified base reader.

Method Summary

Methods

Modifier and Type	Method and Description
void	addCoreClosedListener(AtomicReader.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.
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(AtomicReader.CoreClosedListener listener) Expert: removes a CoreClosedListener from this reader's shared core
String	toString()
static AtomicReader	unwrap(AtomicReader reader) Get the wrapped instance by reader as long as this reader is an intance of FilterAtomicReader.

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

addCoreClosedListenerAsReaderClosedListener, docFreq, getContext, getDocCount, getSumDocFreq, getSumTotalTermFreq, hasNorms, removeCoreClosedListenerAsReaderClosedListener, termDocsEnum, termPositionsEnum, 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, open, open, open, open, open, registerParentReader, removeReaderClosedListener, tryIncRef

Methods inherited from class java.lang.Object

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

Field Detail

in

protected final AtomicReader in

The underlying AtomicReader.

Constructor Detail

FilterAtomicReader

public FilterAtomicReader(AtomicReader in)

Construct a FilterAtomicReader based on the specified base reader.

Note that base reader is closed if this FilterAtomicReader is closed.

Parameters:

in - specified base reader.

Method Detail

unwrap

public static AtomicReader unwrap(AtomicReader reader)

Get the wrapped instance by reader as long as this reader is an intance of FilterAtomicReader.

addCoreClosedListener

public void addCoreClosedListener(AtomicReader.CoreClosedListener listener)

Description copied from class: AtomicReader

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

Specified by:

addCoreClosedListener in class AtomicReader

removeCoreClosedListener

public void removeCoreClosedListener(AtomicReader.CoreClosedListener listener)

Description copied from class: AtomicReader

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

Specified by:

removeCoreClosedListener in class AtomicReader

getLiveDocs

public Bits getLiveDocs()

Description copied from class: AtomicReader

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 AtomicReader

getFieldInfos

public FieldInfos getFieldInfos()

Description copied from class: AtomicReader

Get the FieldInfos describing all fields in this reader.

Specified by:

getFieldInfos in class AtomicReader

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

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

doClose

protected void doClose()
                throws IOException

Description copied from class: IndexReader

Implements close.

Specified by:

doClose in class IndexReader

Throws:

IOException

fields

public Fields fields()
              throws IOException

Description copied from class: AtomicReader

Returns Fields for this reader. This method may return null if the reader has no postings.

Specified by:

fields in class AtomicReader

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object

getNumericDocValues

public NumericDocValues getNumericDocValues(String field)
                                     throws IOException

Description copied from class: AtomicReader

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 AtomicReader

Throws:

IOException

getBinaryDocValues

public BinaryDocValues getBinaryDocValues(String field)
                                   throws IOException

Description copied from class: AtomicReader

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 AtomicReader

Throws:

IOException

getSortedDocValues

public SortedDocValues getSortedDocValues(String field)
                                   throws IOException

Description copied from class: AtomicReader

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 AtomicReader

Throws:

IOException

getSortedNumericDocValues

public SortedNumericDocValues getSortedNumericDocValues(String field)
                                                 throws IOException

Description copied from class: AtomicReader

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 AtomicReader

Throws:

IOException

getSortedSetDocValues

public SortedSetDocValues getSortedSetDocValues(String field)
                                         throws IOException

Description copied from class: AtomicReader

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 AtomicReader

Throws:

IOException

getNormValues

public NumericDocValues getNormValues(String field)
                               throws IOException

Description copied from class: AtomicReader

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 AtomicReader

Throws:

IOException

getDocsWithField

public Bits getDocsWithField(String field)
                      throws IOException

Description copied from class: AtomicReader

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 AtomicReader

Throws:

IOException

checkIntegrity

public void checkIntegrity()
                    throws IOException

Description copied from class: AtomicReader

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 AtomicReader

Throws:

IOException