Module org.apache.lucene.analysis.common

Package org.apache.lucene.analysis.ru

Class RussianAnalyzer

java.lang.Object

org.apache.lucene.analysis.Analyzer

org.apache.lucene.analysis.StopwordAnalyzerBase

org.apache.lucene.analysis.ru.RussianAnalyzer

All Implemented Interfaces:

Closeable, AutoCloseable

public final class RussianAnalyzer
extends StopwordAnalyzerBase

Analyzer for Russian language.

Supports an external list of stopwords (words that will not be indexed at all). A default set of stopwords is used unless an alternative list is specified.

Since:

3.1

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	RussianAnalyzer.DefaultSetHolder

Nested classes/interfaces inherited from class org.apache.lucene.analysis.Analyzer

Analyzer.ReuseStrategy, Analyzer.TokenStreamComponents

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DEFAULT_STOPWORD_FILE	File containing default Russian stopwords.
private final CharArraySet	stemExclusionSet

Fields inherited from class org.apache.lucene.analysis.StopwordAnalyzerBase

stopwords

Fields inherited from class org.apache.lucene.analysis.Analyzer

GLOBAL_REUSE_STRATEGY, PER_FIELD_REUSE_STRATEGY

Constructor Summary

Constructors

Constructor	Description
RussianAnalyzer()
RussianAnalyzer(CharArraySet stopwords)	Builds an analyzer with the given stop words
RussianAnalyzer(CharArraySet stopwords, CharArraySet stemExclusionSet)	Builds an analyzer with the given stop words

Method Summary

Modifier and Type	Method	Description
protected Analyzer.TokenStreamComponents	createComponents(String fieldName)	Creates Analyzer.TokenStreamComponents used to tokenize all the text in the provided Reader.
static CharArraySet	getDefaultStopSet()	Returns an unmodifiable instance of the default stop-words set.
protected TokenStream	normalize(String fieldName, TokenStream in)	Wrap the given TokenStream in order to apply normalization filters.

Methods inherited from class org.apache.lucene.analysis.StopwordAnalyzerBase

getStopwordSet, loadStopwordSet, loadStopwordSet, loadStopwordSet

Methods inherited from class org.apache.lucene.analysis.Analyzer

attributeFactory, close, getOffsetGap, getPositionIncrementGap, getReuseStrategy, initReader, initReaderForNormalization, normalize, tokenStream, tokenStream

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_STOPWORD_FILE

public static final String DEFAULT_STOPWORD_FILE

File containing default Russian stopwords.

See Also:

• Constant Field Values

stemExclusionSet

private final CharArraySet stemExclusionSet

Constructor Details

RussianAnalyzer

public RussianAnalyzer()

RussianAnalyzer

public RussianAnalyzer(CharArraySet stopwords)

Builds an analyzer with the given stop words

Parameters:

stopwords - a stopword set

RussianAnalyzer

public RussianAnalyzer(CharArraySet stopwords,
 CharArraySet stemExclusionSet)

Builds an analyzer with the given stop words

Parameters:

stopwords - a stopword set

stemExclusionSet - a set of words not to be stemmed

Method Details

getDefaultStopSet

public static CharArraySet getDefaultStopSet()

Returns an unmodifiable instance of the default stop-words set.

Returns:

an unmodifiable instance of the default stop-words set.

createComponents

protected Analyzer.TokenStreamComponents createComponents(String fieldName)

Creates Analyzer.TokenStreamComponents used to tokenize all the text in the provided Reader.

Specified by:

createComponents in class Analyzer

Parameters:

fieldName - the name of the fields content passed to the Analyzer.TokenStreamComponents sink as a reader

Returns:

Analyzer.TokenStreamComponents built from a StandardTokenizer filtered with LowerCaseFilter, StopFilter, SetKeywordMarkerFilter if a stem exclusion set is provided, and SnowballFilter

normalize

protected TokenStream normalize(String fieldName,
 TokenStream in)

Description copied from class: Analyzer

Wrap the given TokenStream in order to apply normalization filters. The default implementation returns the TokenStream as-is. This is used by Analyzer.normalize(String, String).

Overrides:

normalize in class Analyzer