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对数据库中的数据进行索引

对数据库中的数据进行索引

作者: 尚亦汐 | 来源:发表于2016-07-22 08:46 被阅读0次
    • 创建一个名为test的数据库,按照下面建表语句创建表:
    CREATE TABLE `authors` (
       `Au_id` varchar(11) NOT NULL,
       `Au_name` varchar(45) DEFAULT NULL,
       `Phone` char(12) DEFAULT NULL,
       PRIMARY KEY (`Au_id`)
     ) ENGINE=InnoDB DEFAULT CHARSET=utf8
    

    在表中插入如下数据:

    • 数据库连接类DBHelpler.java:
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.PreparedStatement;
    import java.sql.SQLException;
    
    public class DBHelper {
        public static final String url = "jdbc:mysql://localhost:3306/test";
        public static final String name = "com.mysql.jdbc.Driver";
        public static final String user = "root";
        public static final String password = "abc123";
    
        public Connection conn = null;
        public PreparedStatement pst = null;
    
        public DBHelper(String sql) {
            try {
                Class.forName(name);//指定连接类型
                conn = DriverManager.getConnection(url, user, password);//获取连接
                pst = conn.prepareStatement(sql);//准备执行语句
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    
        public void close() {
            try {
                this.conn.close();
                this.pst.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
    
    • TestLucene.java
    import java.io.IOException;
    import java.nio.file.Paths;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    
    import org.apache.lucene.search.Query;
    import org.apache.lucene.search.ScoreDoc;
    import org.apache.lucene.analysis.Analyzer;
    import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer;
    import org.apache.lucene.document.Document;
    import org.apache.lucene.document.Field;
    import org.apache.lucene.document.StringField;
    import org.apache.lucene.index.DirectoryReader;
    import org.apache.lucene.index.IndexReader;
    import org.apache.lucene.index.IndexWriter;
    import org.apache.lucene.index.IndexWriterConfig;
    import org.apache.lucene.index.IndexWriterConfig.OpenMode;
    import org.apache.lucene.queryparser.classic.ParseException;
    import org.apache.lucene.queryparser.classic.QueryParser;
    import org.apache.lucene.search.IndexSearcher;
    import org.apache.lucene.search.TopDocs;
    import org.apache.lucene.store.Directory;
    import org.apache.lucene.store.FSDirectory;
    
    public class TestLucene {
    
        static String sql = null;
        static DBHelper db1 = null;
        static ResultSet ret = null;
        String indexPath = "D:\\lucene\\index";
    
        /**
         * 获取数据库中的数据,返回ResultSet
         * 
         * @param sql 需要执行的sql语句
         */
    
        public ResultSet getResult(String sql) {
            db1 = new DBHelper(sql);// 创建DBHelper对象
            try {
                ret = db1.pst.executeQuery(sql);
                return ret;
            } catch (Exception e) {
                System.out.println(e);
            }
            return null;
        }
    
        public Analyzer getAnalyzer() {
            return new SmartChineseAnalyzer();
        }
    
        /**
         * 为数据库的数据建立索引
         * 
         * @param rs
         *            从数据库中返回的数据
         * @throws IOException
         * @throws SQLException
         */
        public void Index(ResultSet rs) throws IOException, SQLException {
            Directory directory = FSDirectory.open(Paths.get(indexPath));
            Analyzer analyzer = getAnalyzer();
            IndexWriterConfig iwc = new IndexWriterConfig(analyzer);
            iwc.setOpenMode(OpenMode.CREATE);
            IndexWriter writer = new IndexWriter(directory, iwc);
    
            while (rs.next()) {
                Document document = new Document();
                Field field = new StringField("id", rs.getString("au_id"), Field.Store.YES);
                document.add(field);
                field = new StringField("name", rs.getString("au_name"), Field.Store.YES);
                document.add(field);
                field = new StringField("phone", rs.getString("Phone"), Field.Store.YES);
                document.add(field);
                writer.addDocument(document);
                System.out.println(
                        "adding: " + rs.getString("au_id") + "\t" + rs.getString("au_name") + "\t" + rs.getString("Phone"));
            }
            writer.close();
        }
        /**
         * 查询
         * 
         * @throws IOException
         * @throws ParseException
         */
        public void seacher(String queryString) throws IOException, ParseException {
            String defualtField = "id";
            TopDocs topDocs = null;
    
            IndexReader reader = DirectoryReader.open(FSDirectory.open(Paths.get(indexPath)));
            IndexSearcher searcher = new IndexSearcher(reader);
    
            Analyzer analyzer = getAnalyzer();
    
            QueryParser queryParser = new QueryParser(defualtField, analyzer);
            Query query = queryParser.parse(queryString);
    
            topDocs = searcher.search(query, 10);
    
            ScoreDoc[] hits = topDocs.scoreDocs;
            for (ScoreDoc hit : hits) {
                Document hitDoc = searcher.doc(hit.doc);
                System.out.println(hitDoc.get(defualtField) 
                            + " " + hitDoc.get("name"));
            }
        }
    
    }
    
    • 测试类Test.java:
    import java.io.IOException;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    
    import org.apache.lucene.queryparser.classic.ParseException;
    
    public class Test {
    
        public static void main(String[] args) throws IOException, SQLException, ParseException {
            TestLucene test=new TestLucene();
            String sql="select * from Authors";
            ResultSet rs=test.getResult(sql);
            test.Index(rs);
            test.seacher("2");
        }
    }
    

    运行结果:

    • 查看索引
        使用查看lucene索引的工具——luke[2],下载的时候要下载跟当前lucene对应版本的luke,否则会无法读取。Luke的界面如下:

    参考资料:

    [1]http://www.cnblogs.com/sleeper-qp/archive/2012/12/20/2827238.html
    [2] https://github.com/DmitryKey/luke/releases
    [3] 罗刚. 解密搜索引擎技术实战--LUCENE & JAVA精华版(第3版)[M]. 电子工业出版社, 2016.

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