org.apache.lucene.analysis.nl

Class DutchAnalyzer

java.lang.Object

org.apache.lucene.analysis.Analyzer

org.apache.lucene.analysis.nl.DutchAnalyzer

All Implemented Interfaces:

Closeable, AutoCloseable

public final class DutchAnalyzer
extends Analyzer

Analyzer for Dutch language.

Supports an external list of stopwords (words that will not be indexed at all), an external list of exclusions (word that will not be stemmed, but indexed) and an external list of word-stem pairs that overrule the algorithm (dictionary stemming). A default set of stopwords is used unless an alternative list is specified, but the exclusion list is empty by default.

Since:

3.1

Nested Class Summary

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

Analyzer.ReuseStrategy, Analyzer.TokenStreamComponents

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_STOPWORD_FILE File containing default Dutch stopwords.

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

GLOBAL_REUSE_STRATEGY, PER_FIELD_REUSE_STRATEGY

Constructor Summary

Constructors

Constructor and Description
DutchAnalyzer() Builds an analyzer with the default stop words (getDefaultStopSet()) and a few default entries for the stem exclusion table.
DutchAnalyzer(CharArraySet stopwords)
DutchAnalyzer(CharArraySet stopwords, CharArraySet stemExclusionTable)
DutchAnalyzer(CharArraySet stopwords, CharArraySet stemExclusionTable, CharArrayMap<String> stemOverrideDict)

Method Summary

Modifier and Type	Method and Description
protected Analyzer.TokenStreamComponents	createComponents(String fieldName) Returns a (possibly reused) TokenStream which tokenizes 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)

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

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

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_STOPWORD_FILE

public static final String DEFAULT_STOPWORD_FILE

File containing default Dutch stopwords.

See Also:

Constant Field Values

Constructor Detail

DutchAnalyzer

public DutchAnalyzer()

Builds an analyzer with the default stop words (getDefaultStopSet()) and a few default entries for the stem exclusion table.

DutchAnalyzer

public DutchAnalyzer(CharArraySet stopwords)

DutchAnalyzer

public DutchAnalyzer(CharArraySet stopwords,
                     CharArraySet stemExclusionTable)

DutchAnalyzer

public DutchAnalyzer(CharArraySet stopwords,
                     CharArraySet stemExclusionTable,
                     CharArrayMap<String> stemOverrideDict)

Method Detail

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)

Returns a (possibly reused) TokenStream which tokenizes all the text in the provided Reader.

Specified by:

createComponents in class Analyzer

Returns:

A TokenStream built from a StandardTokenizer filtered with LowerCaseFilter, StopFilter, SetKeywordMarkerFilter if a stem exclusion set is provided, StemmerOverrideFilter, and SnowballFilter

normalize

protected TokenStream normalize(String fieldName,
                                TokenStream in)

Overrides:

normalize in class Analyzer