如果用JDBC 来查询学生成绩单, 你可以写出主要代码吗？

主要是看异常的处理
Connection cn = null;

PreparedStatement pstmt =null;

Resultset rs = null;

try

{

    Class.forname(driveClassName);

    cn =  DriverManager.getConnection(url,username,password);

    pstmt = cn.prepareStatement(“select  score.* from score ,student “ +

        “where score.stuId = student.id and student.name = ?”);

    pstmt.setString(1,studentName);

    Resultset rs = pstmt.executeQuery();

    while(rs.next())

    {

        system.out.println(rs.getInt(“subject”)  +  “    ” + rs.getFloat(“score”) );

    }

}catch(Exception e){e.printStackTrace();}

finally

{

    if(rs != null) try{ rs.close() }catch(exception e){}

    if(pstmt != null) try{pstmt.close()}catch(exception e){}

    if(cn != null) try{ cn.close() }catch(exception e){}

}