java lucene词干提取_lucene 进行去除停用词和词干提取

好的，您可以使用Lucene的分词器和过滤器来进行去除停用词和词干提取。以下是一个示例代码：

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.en.EnglishAnalyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
import org.apache.lucene.analysis.tokenattributes.OffsetAttribute;
import org.apache.lucene.analysis.tokenattributes.TypeAttribute;
import org.apache.lucene.util.Version;

import java.io.IOException;
import java.io.StringReader;

public class LuceneStemmingDemo {

    public static void main(String[] args) throws IOException {

        // 原始文本
        String text = "Lucene is a Java full-text search engine. " +
                "Lucene is not a complete application, but rather a code library " +
                "and API that can easily be used to add search capabilities to applications.";

        // 创建分词器
        Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_6_6_0);

        // 创建 TokenStream
        StringReader reader = new StringReader(text);
        TokenStream tokenStream = analyzer.tokenStream("", reader);

        // 创建词干提取器
        PorterStemmer porterStemmer = new PorterStemmer();

        // 添加过滤器
        tokenStream = new StopFilter(tokenStream, EnglishAnalyzer.getDefaultStopSet()); // 去除停用词
        tokenStream = new PorterStemFilter(tokenStream); // 进行词干提取

        // 获取词汇单元属性
        CharTermAttribute charTermAttribute = tokenStream.addAttribute(CharTermAttribute.class);

        // 获取位移属性
        OffsetAttribute offsetAttribute = tokenStream.addAttribute(OffsetAttribute.class);

        // 获取类型属性
        TypeAttribute typeAttribute = tokenStream.addAttribute(TypeAttribute.class);

        // 遍历 TokenStream
        tokenStream.reset();
        while (tokenStream.incrementToken()) {
            System.out.println("词汇单元：" + charTermAttribute.toString() +
                    ", 起始位置：" + offsetAttribute.startOffset() +
                    ", 结束位置：" + offsetAttribute.endOffset() +
                    ", 词性：" + typeAttribute.type());

            // 进行词干提取
            porterStemmer.setCurrent(charTermAttribute.toString());
            porterStemmer.stem();
            String stem = porterStemmer.getCurrent();
            System.out.println("词干：" + stem);
        }
        tokenStream.close();
        analyzer.close();
    }
}

在上面的代码中，我们使用了`StandardAnalyzer`作为分词器，使用`EnglishAnalyzer.getDefaultStopSet()`作为停用词集合，使用`PorterStemFilter`作为词干提取器。在遍历`TokenStream`的过程中，我们调用了`PorterStemmer`的`stem()`方法进行词干提取。最后，记得关闭`TokenStream`和分词器。