7、索引庫的查詢一之：簡單查詢

1.1  TermQuery

只需要指定要搜索的域和要搜索的關鍵詞就可以搜索。

//使用TermQuery查詢
@Test
public void testTermQuery() throws Exception {
    //以讀的方式打開索引庫
    Directory directory = FSDirectory.open(Paths.get("D:\\LucentTest\\luceneIndex"));
    //創建一個IndexReader
    IndexReader indexReader = DirectoryReader.open(directory);
    //創建一個IndexSearcher對象
    IndexSearcher indexSearcher = new IndexSearcher(indexReader);
    //創建一個查詢對象
    Query query = new TermQuery(new Term("content", "java"));
    //執行查詢
    TopDocs topDocs = indexSearcher.search(query, 10);
    System.out.println("查詢結果總數量：" + topDocs.totalHits);
    for (ScoreDoc scoreDoc : topDocs.scoreDocs) {
        //取document對象
        Document document = indexSearcher.doc(scoreDoc.doc);
        System.out.println(document.get("name"));
        System.out.println(document.get("path"));
    }
    indexReader.close();
}

1.2  MatchAllDocsQuery

//匹配所有文檔
@Test
public void testMatchAllDocsQuery() throws Exception {
    //以讀的方式打開索引庫
    Directory directory = FSDirectory.open(Paths.get("D:\\LucentTest\\luceneIndex"));
    //創建一個IndexReader
    IndexReader indexReader = DirectoryReader.open(directory);
    //創建一個IndexSearcher對象
    IndexSearcher indexSearcher = new IndexSearcher(indexReader);
    //創建一查詢對象
    Query query = new MatchAllDocsQuery();
    //執行查詢
    //執行查詢
    TopDocs topDocs = indexSearcher.search(query, 10);
    System.out.println("查詢結果總數量：" + topDocs.totalHits);
    for (ScoreDoc scoreDoc : topDocs.scoreDocs) {
        //取document對象
        Document document = indexSearcher.doc(scoreDoc.doc);
        System.out.println(document.get("name"));
        //System.out.println(document.get("content"));
        System.out.println(document.get("path"));
        System.out.println(document.get("size"));
    }
    indexSearcher.getIndexReader().close();
}

//不匹配所有文檔
@Test
public void testMatchNoDocsQuery() throws Exception {
    //以讀的方式打開索引庫
    Directory directory = FSDirectory.open(Paths.get("D:\\LucentTest\\luceneIndex"));
    //創建一個IndexReader
    IndexReader indexReader = DirectoryReader.open(directory);
    //創建一個IndexSearcher對象
    IndexSearcher indexSearcher = new IndexSearcher(indexReader);
    //創建一查詢對象
    Query query = new MatchNoDocsQuery();
    //執行查詢
    //執行查詢
    TopDocs topDocs = indexSearcher.search(query, 10);
    System.out.println("查詢結果總數量：" + topDocs.totalHits);
    for (ScoreDoc scoreDoc : topDocs.scoreDocs) {
        //取document對象
        Document document = indexSearcher.doc(scoreDoc.doc);
        System.out.println(document.get("name"));
    }
    indexSearcher.getIndexReader().close();
}

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