lucene 7.x 排序

一.创建索引

 @Test
     public void indexCreate() throws IOException {
         //创建分词器
         Analyzer analyzer = new StandardAnalyzer();
         IndexWriterConfig config = new IndexWriterConfig(analyzer);

         //指定索引存放目录以及配置参数
         Directory directory =FSDirectory.open(Paths.get("F:/luceneIndex"));
         IndexWriter writer = new IndexWriter(directory,config);

         //采集数据
         List<Book> bookList = bookDao.findAll();
         /*for (Book book : bookList) {
             System.out.println(book.getName());
         }*/
         //将采集的数据封装到Document中
         Document doc = null;
         for (Book book : bookList) {
             doc  = new Document();
              // store:如果是yes，则说明存储到文档域中
             //id:不分词,索引,存储
             Field id = new StringField("id",book.getId().toString(),Store.YES);

             //name:分词,索引,存储
             Field name = new TextField("name",book.getName(),Store.YES);
             //price:不分词,索引,存储,
             Field price = new FloatPoint("price",book.getPrice());

             //pic:不分词,不索引,存储,存储要添加一个同名的StoredField
             Field pic   = new StoredField("pic",book.getPic());
             //desciption:分词,索引,不存储
             Field description = new TextField("description",book.getDescription(),Store.NO);
             doc.add(id);
             doc.add(name);
             doc.add(price);
             doc.add(new StoredField("price",book.getPrice()));//存储
             doc.add(new NumericDocValuesField("price",book.getPrice().longValue()));//排序
             doc.add(pic);
             doc.add(description);

             //生成索引
             writer.addDocument(doc);
         }

         //关闭
         writer.close();
     }

注意:创建索引时,对应price采用了FloatPoint,如果要对此字段进行存储,要添加同名的StoredField,如果要对此字段进行排序,要添加同名的NumericDocValuesField,

否则会报unexpected docvalues type异常

二.排序

 //查询
     @Test
     public void indexSearch() throws IOException, ParseException {
         String[] fields = {"name","description"};
         MultiFieldQueryParser parser = new MultiFieldQueryParser(fields,new StandardAnalyzer());
         Query query = parser.parse("lucene");
         query = parser.parse("java");
         doSearch(query);
     }

     private void doSearch (Query query) {
         Directory directory;
         try {
             directory = FSDirectory.open(Paths.get("F:/luceneIndex"));

         IndexReader reader = DirectoryReader.open(directory);
         //创建IndexSearcher
         IndexSearcher searcher = new IndexSearcher(reader);
         //true表示降序
         //SortField.Type.SCORE  根据相关度进行排序(默认)
         //SortField.Type.DOC    根据文档编号或者说是索引顺序
         //SortField.Type.FLOAT(Long等),根据fieldName的数值类型进行排序
         SortField sortField = new SortField("price",SortField.Type.FLOAT,true);
         Sort sort = new Sort(sortField);
         TopDocs topDocs = searcher.search(query,10,sort);
         long count = topDocs.totalHits;
         System.out.println("匹配的总条数是----" + count);

         //根据相关度排序后的结果
         ScoreDoc[] docs = topDocs.scoreDocs;
         for (ScoreDoc scoreDoc : docs) {
             int docId = scoreDoc.doc;
             Document document = searcher.doc(docId);
             System.out.println("id----"+document.get("id"));
             System.out.println("name----"+document.get("name"));
             System.out.println("price----"+document.get("price"));
             /*System.out.println("pic----"+document.get("pic"));
             System.out.println("description----"+document.get("description"));*/
             System.out.println("======================");
         }
         reader.close();
         } catch (IOException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }

     }

此外还有

//Sort.RELEVANCE 根据相关度排序
//Sort.INDEXORDER 根据索引顺序排序
TopDocs topDocs = searcher.search(query,10,Sort.INDEXORDER);