Lucene自定义评分查询 

  1 package com.lucene.score;
  2 
  3 import java.io.IOException;
  4 import java.sql.Date;
  5 import java.text.SimpleDateFormat;
  6 
  7 import org.apache.lucene.document.Document;
  8 import org.apache.lucene.index.CorruptIndexException;
  9 import org.apache.lucene.index.IndexReader;
 10 import org.apache.lucene.index.Term;
 11 import org.apache.lucene.search.FieldCache;
 12 import org.apache.lucene.search.IndexSearcher;
 13 import org.apache.lucene.search.Query;
 14 import org.apache.lucene.search.ScoreDoc;
 15 import org.apache.lucene.search.TermQuery;
 16 import org.apache.lucene.search.TopDocs;
 17 import org.apache.lucene.search.function.CustomScoreProvider;
 18 import org.apache.lucene.search.function.CustomScoreQuery;
 19 import org.apache.lucene.search.function.FieldScoreQuery;
 20 import org.apache.lucene.search.function.FieldScoreQuery.Type;
 21 import org.apache.lucene.search.function.ValueSourceQuery;
 22 
 23 import com.lucene.search.IndexUtils;
 24 
 25 public class MyCustomScore {
 26     public void searchByScoreQuery() {
 27         try {
 28             IndexSearcher searcher = new IndexSearcher(
 29                     IndexReader.open(IndexUtils.getDirectory()));
 30             Query q = new TermQuery(new Term("content", "1"));
 31             // 1.创建评分域
 32             FieldScoreQuery fieldScoreQuery = new FieldScoreQuery("size",
 33                     Type.INT);
 34             // 2.根据评分域和原有的query创建自定义的query对象
 35             // 2.1 创建MyCustomScoreQuery继承CustomScoreQuery
 36             // 2.2重写getCustomScoreProvider方法
 37             // 2.3创建MyCustomScoreProvider继承CustomScoreProvider
 38             // 2.4重写customScore方法,自定义评分算法
 39             MyCustomScoreQuery query = new MyCustomScoreQuery(q,
 40                     fieldScoreQuery);
 41             TopDocs docs=searcher.search(query, 30);
 42             // 输出信息
 43             ScoreDoc[] sds = docs.scoreDocs;
 44             Document d = null;
 45             SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
 46             for (ScoreDoc s : sds) {
 47                 d = searcher.doc(s.doc);
 48                 System.out.println(s.doc + "->" + s.score + "->"
 49                         + d.get("filename") + "->" + d.get("size") + "->"
 50                         + sdf.format(new Date(Long.valueOf(d.get("date")))));
 51             }
 52 
 53         } catch (CorruptIndexException e) {
 54             e.printStackTrace();
 55         } catch (IOException e) {
 56             e.printStackTrace();
 57         }
 58     }
 59 }
 60 
 61 @SuppressWarnings("serial")
 62 class MyCustomScoreQuery extends CustomScoreQuery {
 63 
 64     public MyCustomScoreQuery(Query subQuery, ValueSourceQuery valSrcQuery) {
 65         super(subQuery, valSrcQuery);
 66     }
 67 
 68     @Override
 69     protected CustomScoreProvider getCustomScoreProvider(IndexReader reader)
 70             throws IOException {
 71         // 默认情况评分是根据原有的评分*传入进来的评分
 72         //return super.getCustomScoreProvider(reader);
 73         
 74         return new MyCustomScoreProvider(reader);
 75     }
 76 }
 77 
 78 class MyCustomScoreProvider extends CustomScoreProvider {
 79 
 80     String[] filenames = null;
 81 
 82     public MyCustomScoreProvider(IndexReader reader) {
 83         super(reader);
 84         try {
 85             filenames = FieldCache.DEFAULT.getStrings(reader, "filename");
 86         } catch (IOException e) {
 87             e.printStackTrace();
 88         }
 89     }
 90 
 91     @Override
 92     public float customScore(int doc, float subQueryScore, float valSrcScore)
 93             throws IOException {
 94         // 根据doc获取文件名
 95         String filename = filenames[doc];
 96         //判断文件后缀是否为txt结尾,是把评分*10  否则/10
 97         if (filename.endsWith(".txt")) {
 98             return subQueryScore * 10;
 99         } else {
100             return subQueryScore / 10;
101         }
102     }
103 }
    @Test
    public void test01(){
        MyCustomScore score=new MyCustomScore();
        score.searchByScoreQuery();
    }

 

posted @ 2012-04-22 16:09  Paul.Lau  阅读(4920)  评论(1)    收藏  举报