package org.wikibrain.lucene.tokenizers; import org.apache.lucene.analysis.TokenStream; import org.apache.lucene.analysis.Tokenizer; import org.apache.lucene.analysis.core.LowerCaseFilter; import org.apache.lucene.analysis.core.StopFilter; import org.apache.lucene.analysis.en.EnglishAnalyzer; import org.apache.lucene.analysis.en.EnglishPossessiveFilter; import org.apache.lucene.analysis.en.PorterStemFilter; import org.apache.lucene.analysis.miscellaneous.SetKeywordMarkerFilter; import org.apache.lucene.analysis.standard.StandardFilter; import org.apache.lucene.analysis.util.CharArraySet; import org.apache.lucene.util.Version; import org.wikibrain.core.lang.Language; import org.wikibrain.lucene.TokenizerOptions; /** * @author Ari Weiland */ public class EnglishTokenizer extends LanguageTokenizer { protected EnglishTokenizer(Version version, TokenizerOptions options, Language language) { super(version, options, language); } @Override public TokenStream getTokenStream(Tokenizer tokenizer, CharArraySet stemExclusionSet) { TokenStream stream = new StandardFilter(matchVersion, tokenizer); if (caseInsensitive) { stream = new LowerCaseFilter(matchVersion, stream); } if (useStopWords) { stream = new StopFilter(matchVersion, stream, EnglishAnalyzer.getDefaultStopSet()); } if (useStem) { if (!stemExclusionSet.isEmpty()) stream = new SetKeywordMarkerFilter(stream, stemExclusionSet); stream = new EnglishPossessiveFilter(matchVersion, stream); stream = new PorterStemFilter(stream); } return stream; } }