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HomeDatabaseMysql TutorialLucene学习总结之三:Lucene的索引文件格式(2)

IndexWriter writer = new IndexWriter(FSDirectory.open(INDEX_DIR), new StandardAnalyzer(Version.LUCENE_CURRENT), true, IndexWriter.MaxFieldLength.LIMITED); writer.setUseCompoundFile(false); indexDocs(writer, docDir); writer.flush(); //flush

      IndexWriter writer = new IndexWriter(FSDirectory.open(INDEX_DIR), new StandardAnalyzer(Version.LUCENE_CURRENT), true, IndexWriter.MaxFieldLength.LIMITED);
      writer.setUseCompoundFile(false);

   
      indexDocs(writer, docDir);
      writer.flush();

//flush生成segment "_0",并且flush函数中,flushDocStores设为false,也即下个段将同本段共享域和词向量信息,这时DocumentsWriter中的docStoreSegment= "_0"。

      indexDocs(writer, docDir);
      writer.commit();

//commit生成segment "_1",由于上次flushDocStores设为false,于是段"_1"的域以及词向量信息是保存在"_0"中的,在这个时刻,段"_1"并不生成自己的"_1.fdx"和"_1.fdt"。然而在commit函数中,flushDocStores设为true,也即下个段将单独使用新的段来存储域和词向量信息。然而这时,DocumentsWriter中的docStoreSegment= "_1",也即当段"_2"存储其域和词向量信息的时候,是存在"_1.fdx"和"_1.fdt"中的,而段"_1"的域和词向量信息却是存在"_0.fdt"和"_0.fdx"中的,这一点非常令人困惑。 如图writer.commit的时候,_1.fdt和_1.fdx并没有形成。

Lucene学习总结之三:Lucene的索引文件格式(2)


      indexDocs(writer, docDir);
      writer.flush();

//段"_2"形成,由于上次flushDocStores设为true,其域和词向量信息是新创建一个段保存的,却是保存在_1.fdt和_1.fdx中的,这时候才产生了此二文件。

Lucene学习总结之三:Lucene的索引文件格式(2)


      indexDocs(writer, docDir);
      writer.flush();

//段"_3"形成,由于上次flushDocStores设为false,其域和词向量信息是共享一个段保存的,也是是保存在_1.fdt和_1.fdx中的

      indexDocs(writer, docDir);
      writer.commit();

//段"_4"形成,由于上次flushDocStores设为false,其域和词向量信息是共享一个段保存的,也是是保存在_1.fdt和_1.fdx中的。然而函数commit中flushDocStores设为true,也意味着下一个段将新创建一个段保存域和词向量信息,此时DocumentsWriter中docStoreSegment= "_4",也表明了虽然段"_4"的域和词向量信息保存在了段"_1"中,将来的域和词向量信息却要保存在段"_4"中。此时"_4.fdx"和"_4.fdt"尚未产生。

Lucene学习总结之三:Lucene的索引文件格式(2)    


      indexDocs(writer, docDir);
      writer.flush();

//段"_5"形成,由于上次flushDocStores设为true,其域和词向量信息是新创建一个段保存的,却是保存在_4.fdt和_4.fdx中的,这时候才产生了此二文件。

Lucene学习总结之三:Lucene的索引文件格式(2)


      indexDocs(writer, docDir);
      writer.commit();
      writer.close();

//段"_6"形成,由于上次flushDocStores设为false,其域和词向量信息是共享一个段保存的,也是是保存在_4.fdt和_4.fdx中的

Lucene学习总结之三:Lucene的索引文件格式(2)

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