org.apache.lucene.analysis.de

Class GermanAnalyzer

java.lang.Object

org.apache.lucene.analysis.Analyzer

org.apache.lucene.analysis.util.StopwordAnalyzerBase

org.apache.lucene.analysis.de.GermanAnalyzer

All Implemented Interfaces:

Closeable, AutoCloseable

public final class GermanAnalyzer
extends StopwordAnalyzerBase

Analyzer for German language.

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

You may specify the Version compatibility when creating GermanAnalyzer:

• As of 3.6, GermanLightStemFilter is used for less aggressive stemming.
• As of 3.1, Snowball stemming is done with SnowballFilter, and Snowball stopwords are used by default.

NOTE: This class uses the same Version dependent settings as StandardAnalyzer.

Nested Class Summary

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

Analyzer.GlobalReuseStrategy, Analyzer.PerFieldReuseStrategy, Analyzer.ReuseStrategy, Analyzer.TokenStreamComponents

Field Summary

Fields

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

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

stopwords

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

GLOBAL_REUSE_STRATEGY, PER_FIELD_REUSE_STRATEGY

Constructor Summary

Constructors

Constructor and Description
GermanAnalyzer() Builds an analyzer with the default stop words: getDefaultStopSet().
GermanAnalyzer(CharArraySet stopwords) Builds an analyzer with the given stop words
GermanAnalyzer(CharArraySet stopwords, CharArraySet stemExclusionSet) Builds an analyzer with the given stop words
GermanAnalyzer(Version matchVersion) Deprecated. GermanAnalyzer()
GermanAnalyzer(Version matchVersion, CharArraySet stopwords) Deprecated. GermanAnalyzer(CharArraySet)
GermanAnalyzer(Version matchVersion, CharArraySet stopwords, CharArraySet stemExclusionSet) Deprecated. GermanAnalyzer(CharArraySet,CharArraySet)

Method Summary

Methods

Modifier and Type	Method and Description
protected Analyzer.TokenStreamComponents	createComponents(String fieldName, Reader reader) Creates Analyzer.TokenStreamComponents used to tokenize all the text in the provided Reader.
static CharArraySet	getDefaultStopSet() Returns a set of default German-stopwords

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

getStopwordSet, loadStopwordSet, loadStopwordSet, loadStopwordSet, loadStopwordSet, loadStopwordSet

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

close, getOffsetGap, getPositionIncrementGap, getReuseStrategy, getVersion, initReader, 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 German stopwords.

See Also:

Constant Field Values

Constructor Detail

GermanAnalyzer

public GermanAnalyzer()

Builds an analyzer with the default stop words: getDefaultStopSet().

GermanAnalyzer

@Deprecated
public GermanAnalyzer(Version matchVersion)

Deprecated. GermanAnalyzer()

GermanAnalyzer

public GermanAnalyzer(CharArraySet stopwords)

Builds an analyzer with the given stop words

Parameters:

stopwords - a stopword set

GermanAnalyzer

@Deprecated
public GermanAnalyzer(Version matchVersion,
                         CharArraySet stopwords)

Deprecated. GermanAnalyzer(CharArraySet)

GermanAnalyzer

public GermanAnalyzer(CharArraySet stopwords,
              CharArraySet stemExclusionSet)

Builds an analyzer with the given stop words

Parameters:

stopwords - a stopword set

stemExclusionSet - a stemming exclusion set

GermanAnalyzer

@Deprecated
public GermanAnalyzer(Version matchVersion,
                         CharArraySet stopwords,
                         CharArraySet stemExclusionSet)

Deprecated. GermanAnalyzer(CharArraySet,CharArraySet)

Method Detail

getDefaultStopSet

public static final CharArraySet getDefaultStopSet()

Returns a set of default German-stopwords

Returns:

a set of default German-stopwords

createComponents

protected Analyzer.TokenStreamComponents createComponents(String fieldName,
                                              Reader reader)

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

Specified by:

createComponents in class Analyzer

Returns:

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