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

public final class GermanStemFilter
extends org.apache.lucene.analysis.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 KeywordMarkerFilter or a custom TokenFilter that sets the KeywordAttribute before this TokenStream.

See Also:

KeywordMarkerFilter

Nested Class Summary

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

org.apache.lucene.util.AttributeSource.AttributeFactory, org.apache.lucene.util.AttributeSource.State

Field Summary

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

input

Constructor Summary

GermanStemFilter(org.apache.lucene.analysis.TokenStream in)
Creates a GermanStemFilter instance

GermanStemFilter(org.apache.lucene.analysis.TokenStream in, Set<?> exclusionSet)
Deprecated. use KeywordAttribute with KeywordMarkerFilter instead.

Method Summary

boolean	incrementToken()
void	setExclusionSet(Set<?> exclusionSet) Deprecated. use KeywordAttribute with KeywordMarkerFilter instead.
void	setStemmer(GermanStemmer stemmer) Set a alternative/custom GermanStemmer for this filter.

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

close, end, reset

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

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

Methods inherited from class java.lang.Object

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

Constructor Detail

GermanStemFilter

public GermanStemFilter(org.apache.lucene.analysis.TokenStream in)

Creates a GermanStemFilter instance

Parameters:

in - the source TokenStream

GermanStemFilter

@Deprecated
public GermanStemFilter(org.apache.lucene.analysis.TokenStream in,
                                   Set<?> exclusionSet)

Deprecated. use KeywordAttribute with KeywordMarkerFilter instead.

Builds a GermanStemFilter that uses an exclusion table.

Method Detail

incrementToken

public boolean incrementToken()
                       throws IOException

Specified by:

incrementToken in class org.apache.lucene.analysis.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.

setExclusionSet

@Deprecated
public void setExclusionSet(Set<?> exclusionSet)

Deprecated. use KeywordAttribute with KeywordMarkerFilter instead.

Set an alternative exclusion list for this filter.