org.apache.lucene.analysis.ngram.NGramTokenFilter Java Examples

/**
 * @param fieldName ignored param
 * @param reader contains data to parse
 * @return TokenStream of ngrams
 */
public TokenStream tokenStream(String fieldName, Reader reader) {
    return new NGramTokenFilter(
            new LowerCaseFilter(
                new StandardFilter(
                    new StandardTokenizer(reader))), min_ngram, max_ngram);
}
 

EdgeNGramTokenFilterFactory(Index index, Settings indexSettings, String name, Settings settings) {
    super(index, indexSettings, name, settings);
    this.minGram = settings.getAsInt("min_gram", NGramTokenFilter.DEFAULT_MIN_NGRAM_SIZE);
    this.maxGram = settings.getAsInt("max_gram", NGramTokenFilter.DEFAULT_MAX_NGRAM_SIZE);
    this.side = parseSide(settings.get("side", "front"));
    this.esVersion = org.elasticsearch.Version.indexCreated(indexSettings);
}
 

@SuppressWarnings("deprecation")
@Override
public TokenStream create(TokenStream tokenStream) {
    final Version version = this.version == Version.LUCENE_4_3 ? Version.LUCENE_4_4 : this.version; // we supported it since 4.3
    if (version.onOrAfter(Version.LUCENE_4_3)) {
        return new NGramTokenFilter(tokenStream, minGram, maxGram);
    } else {
        return new Lucene43NGramTokenFilter(tokenStream, minGram, maxGram);
    }
}
 

/**
 * @param fieldName ignored param
 * @param reader contains data to parse
 * @return TokenStream of ngrams
 */
public TokenStream tokenStream(String fieldName, Reader reader) {
    return new NGramTokenFilter(
            new LowerCaseFilter(
                new StandardFilter(
                    new StandardTokenizer(reader))), min_ngram, max_ngram);
}
 

@Override
public List<PreConfiguredTokenFilter> getPreConfiguredTokenFilters() {
    List<PreConfiguredTokenFilter> filters = new ArrayList<>();
    filters.add(PreConfiguredTokenFilter.singleton("apostrophe", false, ApostropheFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("arabic_normalization", true, ArabicNormalizationFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("arabic_stem", false, ArabicStemFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("asciifolding", true, ASCIIFoldingFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("bengali_normalization", true, BengaliNormalizationFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("brazilian_stem", false, BrazilianStemFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("cjk_bigram", false, CJKBigramFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("cjk_width", true, CJKWidthFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("classic", false, ClassicFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton(
        "common_grams",
        false,
        input -> new CommonGramsFilter(input, CharArraySet.EMPTY_SET)));
    filters.add(PreConfiguredTokenFilter.singleton("czech_stem", false, CzechStemFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("decimal_digit", true, DecimalDigitFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("delimited_payload_filter", false, input ->
            new DelimitedPayloadTokenFilter(input,
                    DelimitedPayloadTokenFilterFactory.DEFAULT_DELIMITER,
                    DelimitedPayloadTokenFilterFactory.DEFAULT_ENCODER)));
    filters.add(PreConfiguredTokenFilter.singleton("delimited_payload", false, input ->
            new DelimitedPayloadTokenFilter(input,
                    DelimitedPayloadTokenFilterFactory.DEFAULT_DELIMITER,
                    DelimitedPayloadTokenFilterFactory.DEFAULT_ENCODER)));
    filters.add(PreConfiguredTokenFilter.singleton("dutch_stem", false, input -> new SnowballFilter(input, new DutchStemmer())));
    filters.add(PreConfiguredTokenFilter.singleton(
        "edge_ngram",
        false,
        input -> new EdgeNGramTokenFilter(input, EdgeNGramTokenFilterFactory.SIDE_FRONT, EdgeNGramTokenFilterFactory.SIDE_BACK, EdgeNGramTokenFilter.DEFAULT_PRESERVE_ORIGINAL)));
    filters.add(PreConfiguredTokenFilter.singleton(
        "elision",
        true,
        input -> new ElisionFilter(input, FrenchAnalyzer.DEFAULT_ARTICLES))
    );
    filters.add(PreConfiguredTokenFilter.singleton("french_stem", false, input -> new SnowballFilter(input, new FrenchStemmer())));
    filters.add(PreConfiguredTokenFilter.singleton("german_normalization", true, GermanNormalizationFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("german_stem", false, GermanStemFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("hindi_normalization", true, HindiNormalizationFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("indic_normalization", true, IndicNormalizationFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("keyword_repeat", false, KeywordRepeatFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("kstem", false, KStemFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("length", false, input ->
        new LengthFilter(input, 0, Integer.MAX_VALUE)));  // TODO this one seems useless
    filters.add(PreConfiguredTokenFilter.singleton(
        "limit",
        false,
        input -> new LimitTokenCountFilter(
            input,
            LimitTokenCountFilterFactory.DEFAULT_MAX_TOKEN_COUNT,
            LimitTokenCountFilterFactory.DEFAULT_CONSUME_ALL_TOKENS)
        )
    );
    filters.add(PreConfiguredTokenFilter.singleton("ngram", false, reader -> new NGramTokenFilter(reader, 1, 2, false)));
    filters.add(PreConfiguredTokenFilter.singleton("persian_normalization", true, PersianNormalizationFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("porter_stem", false, PorterStemFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("reverse", false, ReverseStringFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("russian_stem", false, input -> new SnowballFilter(input, "Russian")));
    filters.add(PreConfiguredTokenFilter.singleton("scandinavian_folding", true, ScandinavianFoldingFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("scandinavian_normalization", true, ScandinavianNormalizationFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("shingle", false, input -> {
        TokenStream ts = new ShingleFilter(input);
        /**
         * We disable the graph analysis on this token stream
         * because it produces shingles of different size.
         * Graph analysis on such token stream is useless and dangerous as it may create too many paths
         * since shingles of different size are not aligned in terms of positions.
         */
        ts.addAttribute(DisableGraphAttribute.class);
        return ts;
    }));
    filters.add(PreConfiguredTokenFilter.singleton("snowball", false, input -> new SnowballFilter(input, "English")));
    filters.add(PreConfiguredTokenFilter.singleton("sorani_normalization", true, SoraniNormalizationFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("stemmer", false, PorterStemFilter::new));
    // The stop filter is in lucene-core but the English stop words set is in lucene-analyzers-common
    filters.add(PreConfiguredTokenFilter.singleton("stop", false, input -> new StopFilter(input, EnglishAnalyzer.ENGLISH_STOP_WORDS_SET)));
    filters.add(PreConfiguredTokenFilter.singleton("trim", true, TrimFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("truncate", false, input -> new TruncateTokenFilter(input, 10)));
    filters.add(PreConfiguredTokenFilter.singleton("type_as_payload", false, TypeAsPayloadTokenFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("unique", false, UniqueTokenFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("uppercase", true, UpperCaseFilter::new));
    filters.add(PreConfiguredTokenFilter.singleton("word_delimiter", false, input ->
            new WordDelimiterFilter(input,
                    WordDelimiterFilter.GENERATE_WORD_PARTS
                  | WordDelimiterFilter.GENERATE_NUMBER_PARTS
                  | WordDelimiterFilter.SPLIT_ON_CASE_CHANGE
                  | WordDelimiterFilter.SPLIT_ON_NUMERICS
                  | WordDelimiterFilter.STEM_ENGLISH_POSSESSIVE, null)));
    filters.add(PreConfiguredTokenFilter.singleton("word_delimiter_graph", false, input ->
            new WordDelimiterGraphFilter(input,
                    WordDelimiterGraphFilter.GENERATE_WORD_PARTS
                  | WordDelimiterGraphFilter.GENERATE_NUMBER_PARTS
                  | WordDelimiterGraphFilter.SPLIT_ON_CASE_CHANGE
                  | WordDelimiterGraphFilter.SPLIT_ON_NUMERICS
                  | WordDelimiterGraphFilter.STEM_ENGLISH_POSSESSIVE, null)));
    return filters;
}
 

@Inject
public NGramTokenFilterFactory(Index index, IndexSettingsService indexSettingsService, @Assisted String name, @Assisted Settings settings) {
    super(index, indexSettingsService.getSettings(), name, settings);
    this.minGram = settings.getAsInt("min_gram", NGramTokenFilter.DEFAULT_MIN_NGRAM_SIZE);
    this.maxGram = settings.getAsInt("max_gram", NGramTokenFilter.DEFAULT_MAX_NGRAM_SIZE);
}
 

/**
 * @see org.apache.lucene.analysis.Analyzer#tokenStream(java.lang.String, java.io.Reader)
 */
@Override
public TokenStream tokenStream(String fieldName, Reader reader) {
    return new NGramTokenFilter(new UpperCaseFilter(new SentenceTokenizer(reader)), minTokenLength, maxTokenLength);
}
 

@Override
public TokenStream create(TokenStream tokenStream) {
    return new NGramTokenFilter(tokenStream, minGram, maxGram, false);
}