org.apache.lucene.analysis
Class StopwordAnalyzerBase

java.lang.Object
  org.apache.lucene.analysis.Analyzer
      org.apache.lucene.analysis.ReusableAnalyzerBase
          org.apache.lucene.analysis.StopwordAnalyzerBase

All Implemented Interfaces:

Closeable

Direct Known Subclasses:

ArabicAnalyzer, ArmenianAnalyzer, BasqueAnalyzer, BrazilianAnalyzer, BulgarianAnalyzer, CatalanAnalyzer, CJKAnalyzer, ClassicAnalyzer, DanishAnalyzer, EnglishAnalyzer, FinnishAnalyzer, FrenchAnalyzer, GalicianAnalyzer, GermanAnalyzer, GreekAnalyzer, HindiAnalyzer, HungarianAnalyzer, IndonesianAnalyzer, IrishAnalyzer, ItalianAnalyzer, JapaneseAnalyzer, LatvianAnalyzer, NorwegianAnalyzer, PersianAnalyzer, PolishAnalyzer, PortugueseAnalyzer, RomanianAnalyzer, RussianAnalyzer, SpanishAnalyzer, StandardAnalyzer, StopAnalyzer, SwedishAnalyzer, ThaiAnalyzer, TurkishAnalyzer, UAX29URLEmailAnalyzer

public abstract class StopwordAnalyzerBase
extends ReusableAnalyzerBase

Base class for Analyzers that need to make use of stopword sets.

Nested Class Summary

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

ReusableAnalyzerBase.TokenStreamComponents

Field Summary

protected Version	matchVersion
protected CharArraySet	stopwords An immutable stopword set

Constructor Summary

protected	StopwordAnalyzerBase(Version version) Creates a new Analyzer with an empty stopword set
protected	StopwordAnalyzerBase(Version version, Set<?> stopwords) Creates a new instance initialized with the given stopword set

Method Summary

Set<?>	getStopwordSet() Returns the analyzer's stopword set or an empty set if the analyzer has no stopwords
protected static CharArraySet	loadStopwordSet(boolean ignoreCase, Class<? extends ReusableAnalyzerBase> aClass, String resource, String comment) Creates a CharArraySet from a file resource associated with a class.
protected static CharArraySet	loadStopwordSet(File stopwords, Version matchVersion) Creates a CharArraySet from a file.
protected static CharArraySet	loadStopwordSet(Reader stopwords, Version matchVersion) Creates a CharArraySet from a file.

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

createComponents, initReader, reusableTokenStream, tokenStream

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

close, getOffsetGap, getPositionIncrementGap, getPreviousTokenStream, setPreviousTokenStream

Methods inherited from class java.lang.Object

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

Field Detail

stopwords

protected final CharArraySet stopwords

An immutable stopword set

matchVersion

protected final Version matchVersion

Constructor Detail

StopwordAnalyzerBase

protected StopwordAnalyzerBase(Version version,
                               Set<?> stopwords)

Creates a new instance initialized with the given stopword set

Parameters:

version - the Lucene version for cross version compatibility

stopwords - the analyzer's stopword set

StopwordAnalyzerBase

protected StopwordAnalyzerBase(Version version)

Creates a new Analyzer with an empty stopword set

Parameters:

version - the Lucene version for cross version compatibility

Method Detail

getStopwordSet

public Set<?> getStopwordSet()

Returns the analyzer's stopword set or an empty set if the analyzer has no stopwords

Returns:

the analyzer's stopword set or an empty set if the analyzer has no stopwords

loadStopwordSet

protected static CharArraySet loadStopwordSet(boolean ignoreCase,
                                              Class<? extends ReusableAnalyzerBase> aClass,
                                              String resource,
                                              String comment)
                                       throws IOException

Creates a CharArraySet from a file resource associated with a class. (See Class.getResourceAsStream(String)).

Parameters:

ignoreCase - true if the set should ignore the case of the stopwords, otherwise false

aClass - a class that is associated with the given stopwordResource

resource - name of the resource file associated with the given class

comment - comment string to ignore in the stopword file

Returns:

a CharArraySet containing the distinct stopwords from the given file

Throws:

IOException - if loading the stopwords throws an IOException

loadStopwordSet

protected static CharArraySet loadStopwordSet(File stopwords,
                                              Version matchVersion)
                                       throws IOException

Creates a CharArraySet from a file.

Parameters:

stopwords - the stopwords file to load

matchVersion - the Lucene version for cross version compatibility

Returns:

a CharArraySet containing the distinct stopwords from the given file

Throws:

IOException - if loading the stopwords throws an IOException

loadStopwordSet

protected static CharArraySet loadStopwordSet(Reader stopwords,
                                              Version matchVersion)
                                       throws IOException

Creates a CharArraySet from a file.

Parameters:

stopwords - the stopwords reader to load

matchVersion - the Lucene version for cross version compatibility

Returns:

a CharArraySet containing the distinct stopwords from the given reader

Throws:

IOException - if loading the stopwords throws an IOException