public class JdbcExample{private Connection getConnection(){Connection connection = null;  //初始化Connectiontry{Class.forName("com.mysql.Driver");  //注册驱动
String url = "jdbc:mysql://localhost:3306/mybatis";String user="root";String password="";connection = DriverManager.getConnection(url,user,password);  //注册数据库信息
}catch(ClassNotFoundException|SQLException ex){Logger.getConnection(JdbcExample.class.getName()).log(Level.SEVERE,null,ex);return null;}return connection;}

public User getUser(int id){Connection connection = getConnection();  //获取连接信息PreparedStatement ps = null;  //操作数据库
ResultSet rs = null;  //接收返回的结果try{ps = connection.prepareStatement("select id, userName from user_info where id =?");  ps.setInt(1,id);rs = ps.executeQuery();while(rs.next()){int roleId = rs.getInt("id");String userName = rs.getString("userName"); User user = new User(id,userName);return user;}}catch(SQLException ex){Logger.getConnection(JdbcExample.class.getName()).log(Level.SEVERE,null,ex);}finally{this.close(rs,ps,connection);}return null;}　　//关闭数据库的连接 private void close(ResultSet rs, Statement stmt, Connection connection){try{if(rs!=null&&!rs.isClosed()){rs.close();}}catch(SQLException ex){Logger.getConnection(JdbcExample.class.getName()).log(Level.SEVERE,null,ex);}try{if(stmt!=null&&!stmt.isClosed()){stmt.close();}}catch(SQLException ex){Logger.getConnection(JdbcExample.class.getName()).log(Level.SEVERE,null,ex);}try{if(connection!=null&&!connection.isClosed()){connection.close();}}catch(SQLException ex){Logger.getConnection(JdbcExample.class.getName()).log(Level.SEVERE,null,ex);}}　　//测试public static void main(String[] args){JdbcExample example = new JdbcExample();User user = example.getUser(1);System.err.println("userName=>+"+user.getName());}

}