A TokenFilter that applies GermanLightStemmer to stem German words.

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

Inheritance: TokenFilter
GermanLightStemFilter Class Documentation
Exemple #1
0
        /// <summary>
        /// Creates
        /// <see cref="TokenStreamComponents"/>
        /// used to tokenize all the text in the provided <see cref="TextReader"/>.
        /// </summary>
        /// <returns> <see cref="TokenStreamComponents"/>
        ///         built from a <see cref="StandardTokenizer"/> filtered with
        ///         <see cref="StandardFilter"/>, <see cref="LowerCaseFilter"/>, <see cref="StopFilter"/>,
        ///         <see cref="SetKeywordMarkerFilter"/> if a stem exclusion set is
        ///         provided, <see cref="GermanNormalizationFilter"/> and <see cref="GermanLightStemFilter"/> </returns>
        protected override TokenStreamComponents CreateComponents(string fieldName, TextReader reader)
        {
            Tokenizer   source = new StandardTokenizer(m_matchVersion, reader);
            TokenStream result = new StandardFilter(m_matchVersion, source);

            result = new LowerCaseFilter(m_matchVersion, result);
            result = new StopFilter(m_matchVersion, result, m_stopwords);
            result = new SetKeywordMarkerFilter(result, exclusionSet);
#pragma warning disable 612, 618
            if (m_matchVersion.OnOrAfter(LuceneVersion.LUCENE_36))
            {
                result = new GermanNormalizationFilter(result);
                result = new GermanLightStemFilter(result);
            }
            else if (m_matchVersion.OnOrAfter(LuceneVersion.LUCENE_31))
#pragma warning restore 612, 618
            {
                result = new SnowballFilter(result, new German2Stemmer());
            }
            else
            {
                result = new GermanStemFilter(result);
            }
            return(new TokenStreamComponents(source, result));
        }
Exemple #2
0
        /// <summary>
        /// Creates
        /// <seealso cref="org.apache.lucene.analysis.Analyzer.TokenStreamComponents"/>
        /// used to tokenize all the text in the provided <seealso cref="Reader"/>.
        /// </summary>
        /// <returns> <seealso cref="org.apache.lucene.analysis.Analyzer.TokenStreamComponents"/>
        ///         built from a <seealso cref="StandardTokenizer"/> filtered with
        ///         <seealso cref="StandardFilter"/>, <seealso cref="LowerCaseFilter"/>, <seealso cref="StopFilter"/>
        ///         , <seealso cref="SetKeywordMarkerFilter"/> if a stem exclusion set is
        ///         provided, <seealso cref="GermanNormalizationFilter"/> and <seealso cref="GermanLightStemFilter"/> </returns>
        public override TokenStreamComponents CreateComponents(string fieldName, TextReader reader)
        {
            Tokenizer source = new StandardTokenizer(matchVersion, reader);
            TokenStream result = new StandardFilter(matchVersion, source);
            result = new LowerCaseFilter(matchVersion, result);
            result = new StopFilter(matchVersion, result, stopwords);
            result = new SetKeywordMarkerFilter(result, exclusionSet);
#pragma warning disable 612, 618
            if (matchVersion.OnOrAfter(LuceneVersion.LUCENE_36))
            {
                result = new GermanNormalizationFilter(result);
                result = new GermanLightStemFilter(result);
            }
            else if (matchVersion.OnOrAfter(LuceneVersion.LUCENE_31))
#pragma warning restore 612, 618
            {
                result = new SnowballFilter(result, new German2Stemmer());
            }
            else
            {
                result = new GermanStemFilter(result);
            }
            return new TokenStreamComponents(source, result);
        }