Package org.apache.lucene.analysis.de

Class GermanStemFilter

java.lang.Object

org.apache.lucene.util.AttributeSource

org.apache.lucene.analysis.TokenStream

org.apache.lucene.analysis.TokenFilter

org.apache.lucene.analysis.de.GermanStemFilter

All Implemented Interfaces:

Closeable, AutoCloseable, Unwrappable<TokenStream>

public final class GermanStemFilter
extends TokenFilter

A TokenFilter that stems German words.

It supports a table of words that should not be stemmed at all. The stemmer used can be changed at runtime after the filter object is created (as long as it is a GermanStemmer).

To prevent terms from being stemmed use an instance of SetKeywordMarkerFilter or a custom TokenFilter that sets the KeywordAttribute before this TokenStream.

See Also:

• SetKeywordMarkerFilter

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource

AttributeSource.State

Field Summary

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

input

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

DEFAULT_TOKEN_ATTRIBUTE_FACTORY

Constructor Summary

Constructors

Constructor	Description
GermanStemFilter(TokenStream in)	Creates a GermanStemFilter instance

Method Summary

Modifier and Type	Method	Description
boolean	incrementToken()
void	setStemmer(GermanStemmer stemmer)	Set a alternative/custom GermanStemmer for this filter.

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

close, end, reset, unwrap

Methods inherited from class org.apache.lucene.util.AttributeSource

addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, endAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, removeAllAttributes, restoreState, toString

Methods inherited from class java.lang.Object

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

Constructor Details

GermanStemFilter

public GermanStemFilter(TokenStream in)

Creates a GermanStemFilter instance

Parameters:

in - the source TokenStream

Method Details

incrementToken

public boolean incrementToken()
                       throws IOException

Specified by:

incrementToken in class TokenStream

Returns:

Returns true for next token in the stream, or false at EOS

Throws:

IOException

setStemmer

public void setStemmer(GermanStemmer stemmer)

Set a alternative/custom GermanStemmer for this filter.