java - 读取文本文件并将输出插入到mysql表中

Question

我想读取txt文件内容并将其插入到我的sql表中。

我通过编码做到了这一点，但它显示了一些错误。也通过查询尝试过，但表中显示为空。

查询 -

INSERT INTO patent_uspto_tmp (pinv) VALUES (LOAD_FILE('/home/gaurav/Documents/pinv.txt'));

代码-

    try{
        String arr[]=null;
    String outputFile = "/home/gaurav/Documents/pinv.txt";

    FileReader fileReader = new FileReader(outputFile);
    BufferedReader bufferedReader = new BufferedReader(fileReader);
    String inputLine;
    List<String> lineList = new ArrayList<String>();
    while ((inputLine = bufferedReader.readLine()) != null) {
        lineList.add(inputLine);
    }
    fileReader.close();

    Class.forName("com.mysql.jdbc.Driver");  

    Connection con=DriverManager.getConnection(  
    "jdbc:mysql://localhost:3306/patent","root","india2000");  
    for (int i = 1;i<outputFile.length();i++)
    {
        arr[i]=outputFile.valueOf(i);

         PreparedStatement ps = (PreparedStatement) con.prepareStatement("insert into patent_uspto_tmp (pinv) values(?)");
            ps.setString(1,arr[i]); //  set the param here with the some value
            ps.executeUpdate();
            con.commit();
            con.close(); 
    }
    }
    catch(Exception e)
    {
        throw new RuntimeException(e);//System.out.println(e);

    }  
}
    }  

        error - null pointer exception

Answer 1

尝试使用 PreparedStatement 和 executeUpdate() 以及最后的 commit() 方法，如下所示:

    PreparedStatement ps = con.prepareStatement("insert into patent_uspto_tmp (pinv) values(?)");
    ps.setString(1, "value");//  set the param here with the some value
    ps.executeUpdate();
    con.commit();