基于Luceneshingle英文单词NGramAnalyzer的实现

此例为基于Lucene shingle英文单词BiGram Analyzer的实现

import java.io.Reader;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.LowerCaseFilter;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.WhitespaceTokenizer;
import org.apache.lucene.analysis.shingle.ShingleFilter;
import org.apache.lucene.util.Version;public final class BiGramAnalyzer extends Analyzer {@Overridepublic TokenStream tokenStream(String fieldName, Reader reader) {TokenStream result = new WhitespaceTokenizer(Version.LUCENE_36, reader);result = new LowerCaseFilter(Version.LUCENE_36, result);ShingleFilter shingleFilter = new ShingleFilter(result, 2);shingleFilter.setOutputUnigrams(false);result = shingleFilter;return result;}}

http://searchhub.org/2010/12/17/whats-a-shingle-in-lucene-parlance/