JDBC封装的连接工具类

public class DBUtils {
    private  static String DRIVER;
    private  static String URL;
    private static String USERNAME;
    private static String PASSWORD;

    //然后是主存功能
    static{
        try {
            InputStream in = new BufferedInputStream(new FileInputStream("src/db.properties"));
            Properties p = new Properties();
            p.load(in);
            DRIVER=p.getProperty("driverName");

            URL=p.getProperty("url");
            USERNAME=p.getProperty("userName");
            PASSWORD=p.getProperty("password");

            Class.forName(DRIVER);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    public static Connection getConnection(){
        Connection conn=null;
        try {
            conn = DriverManager.getConnection(URL, USERNAME, PASSWORD);

        } catch (SQLException e) {
           e.printStackTrace();
        }
        return conn;
    }

//    public static void main(String[] args) {
//        Connection connection=getConnection();
//
//    }

}

以及在同级目录下需要创建字段文件夹，并写入字段