Luceneで頻度がnullになる4.4

Question

私はある文書で別の単語の頻度を取得しようとしています。ここ は

package Lucene; 

    import java.io.IOException; 

    import org.apache.lucene.analysis.standard.StandardAnalyzer; 
    import org.apache.lucene.document.Document; 
    import org.apache.lucene.document.Field; 
    import org.apache.lucene.document.StringField; 
    import org.apache.lucene.document.TextField; 
    import org.apache.lucene.index.DirectoryReader; 
    import org.apache.lucene.index.DocsEnum; 
    import org.apache.lucene.index.IndexReader; 
    import org.apache.lucene.index.IndexWriter; 
    import org.apache.lucene.index.IndexWriterConfig; 
    import org.apache.lucene.index.Terms; 
    import org.apache.lucene.index.TermsEnum; 
    import org.apache.lucene.queryparser.classic.QueryParser; 
    import org.apache.lucene.search.DocIdSetIterator; 
    import org.apache.lucene.search.IndexSearcher; 
    import org.apache.lucene.search.Query; 
    import org.apache.lucene.search.ScoreDoc; 
    import org.apache.lucene.search.TopScoreDocCollector; 
    import org.apache.lucene.store.Directory; 
    import org.apache.lucene.store.RAMDirectory; 
    import org.apache.lucene.util.BytesRef; 
    import org.apache.lucene.util.Version; 


    public class LuceneTest 
    { 
     public static void main(String[] args) 
     { 
      Terms terms=null; 
      try 
      { 
       // Specify the analyzer for tokenizing text. 
       // The same analyzer should be used for indexing and searching 
       StandardAnalyzer analyzer = new StandardAnalyzer(Version.LUCENE_44); 

       // Code to create the index 
       Directory index = new RAMDirectory(); 

       IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_44, analyzer); 

       IndexWriter w = new IndexWriter(index, config); 
       addDoc(w, "Lucene in Action", "193398817"); 
       addDoc(w, "Lucene for Dummies", "55320055Z"); 
       addDoc(w, "Managing Gigabytes", "55063554A"); 
       addDoc(w, "The Art of Computer Science", "9900333X"); 
       addDoc(w, "My name is teja", "12842d99"); 
       addDoc(w, "Lucene demo by teja", "23k43413"); 
       w.close(); 

       // Text to search 
       String querystr = args.length > 0 ? args[0] : "teja"; 

       // The \"title\" arg specifies the default field to use when no field is explicitly specified in the query 
       Query q = new QueryParser(Version.LUCENE_44, "title", analyzer).parse(querystr); 

       // Searching code 
       int hitsPerPage = 10; 
       IndexReader reader = DirectoryReader.open(index); 
       IndexSearcher searcher = new IndexSearcher(reader); 
       TopScoreDocCollector collector = TopScoreDocCollector.create(hitsPerPage, true); 
       searcher.search(q, collector); 
       ScoreDoc[] hits = collector.topDocs().scoreDocs; 

       // Code to display the results of search 
       System.out.println("Found " + hits.length + " hits."); 
       for(int i=0;i<hits.length;++i) 
       { 
        int docId = hits[i].doc; 
        System.out.println("docId "+docId); 
        Document d = searcher.doc(docId); 
        System.out.println((i + 1) + ". " + d.get("isbn") + d.get("title")); 
        terms = reader.getTermVector(docId, "title"); //get terms vectors for one document and one field 
        if (terms != null && terms.size() > 0) { 
         TermsEnum termsEnum = terms.iterator(null); // access the terms for this field 
         BytesRef term = null; 
         while ((term = termsEnum.next()) != null) {// explore the terms for this field 
          DocsEnum docsEnum = termsEnum.docs(null, null); // enumerate through documents, in this case only one 
          int docIdEnum; 
          while ((docIdEnum = docsEnum.nextDoc()) != DocIdSetIterator.NO_MORE_DOCS) { 
           System.out.println(term.utf8ToString()+" "+docIdEnum+" "+docsEnum.freq()); //get the term frequency in the document 

          } 
         } 
        } 





       } 


       // reader can only be closed when there is no need to access the documents any more 
       reader.close(); 
      } 
      catch(Exception e) 
      { 
       System.out.println(e.getMessage()); 
      } 
     } 
     private static void addDoc(IndexWriter w, String title, String isbn) throws IOException 
     { 
       Document doc = new Document(); 
       // A text field will be tokenized 
       doc.add(new TextField("title", title, Field.Store.YES)); 
       // We use a string field for isbn because we don\'t want it tokenized 
       doc.add(new StringField("isbn", isbn, Field.Store.YES)); 
       w.addDocument(doc); 
     } 
    } 

をコードスナップですが、私はnull.Canいずれかが私に助けて来て、この直接出力を得る

Found 2 hits. 
docId 4 
1. 12842d99My name is teja 
docId 5 
2. 23k43413Lucene demo by teja 

が、このラインで

 terms = reader.getTermVector(docId, "title"); 

条件を実行していたときにLucene4.4を使用して、doc内の各単語の頻度を助けます。

Answer 1

はTextField documentationを参照してください：

用語ベクトルなしインデックス化とトークン化、されるフィールド。

あなたがTermVectorsを保存したい場合は、あなただけの希望FieldTypeで、Fieldを使用することができます。