Lucene自定义评分查询

package com.lucene.score;

import java.io.IOException;
import java.sql.Date;
import java.text.SimpleDateFormat;

import org.apache.lucene.document.Document;
import org.apache.lucene.index.CorruptIndexException;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.FieldCache;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.search.function.CustomScoreProvider;
import org.apache.lucene.search.function.CustomScoreQuery;
import org.apache.lucene.search.function.FieldScoreQuery;
import org.apache.lucene.search.function.FieldScoreQuery.Type;
import org.apache.lucene.search.function.ValueSourceQuery;

import com.lucene.search.IndexUtils;

public class MyCustomScore {
    public void searchByScoreQuery() {
        try {
            IndexSearcher searcher = new IndexSearcher(
                    IndexReader.open(IndexUtils.getDirectory()));
            Query q = new TermQuery(new Term("content", "1"));
            // 1.创建评分域
            FieldScoreQuery fieldScoreQuery = new FieldScoreQuery("size",
                    Type.INT);
            // 2.根据评分域和原有的query创建自定义的query对象
            // 2.1 创建MyCustomScoreQuery继承CustomScoreQuery
            // 2.2重写getCustomScoreProvider方法
            // 2.3创建MyCustomScoreProvider继承CustomScoreProvider
            // 2.4重写customScore方法,自定义评分算法
            MyCustomScoreQuery query = new MyCustomScoreQuery(q,
                    fieldScoreQuery);
            TopDocs docs=searcher.search(query, 30);
            // 输出信息
            ScoreDoc[] sds = docs.scoreDocs;
            Document d = null;
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
            for (ScoreDoc s : sds) {
                d = searcher.doc(s.doc);
                System.out.println(s.doc + "->" + s.score + "->"
                        + d.get("filename") + "->" + d.get("size") + "->"
                        + sdf.format(new Date(Long.valueOf(d.get("date")))));
            }

        } catch (CorruptIndexException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

@SuppressWarnings("serial")
class MyCustomScoreQuery extends CustomScoreQuery {

    public MyCustomScoreQuery(Query subQuery, ValueSourceQuery valSrcQuery) {
        super(subQuery, valSrcQuery);
    }

    @Override
    protected CustomScoreProvider getCustomScoreProvider(IndexReader reader)
            throws IOException {
        // 默认情况评分是根据原有的评分*传入进来的评分
        //return super.getCustomScoreProvider(reader);
        
        return new MyCustomScoreProvider(reader);
    }
}

class MyCustomScoreProvider extends CustomScoreProvider {

    String[] filenames = null;

    public MyCustomScoreProvider(IndexReader reader) {
        super(reader);
        try {
            filenames = FieldCache.DEFAULT.getStrings(reader, "filename");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public float customScore(int doc, float subQueryScore, float valSrcScore)
            throws IOException {
        // 根据doc获取文件名
        String filename = filenames[doc];
        //判断文件后缀是否为txt结尾,是把评分*10  否则/10
        if (filename.endsWith(".txt")) {
            return subQueryScore * 10;
        } else {
            return subQueryScore / 10;
        }
    }
}

    @Test
    public void test01(){
        MyCustomScore score=new MyCustomScore();
        score.searchByScoreQuery();
    }