mysql中关于分页查询的输出问题！

String sql = "select * from emp order by empno limit ?,?";
prepareStatement stmt = con.prepareStatement(sql);
stmt.setInt(1, begin);
stmt.setInt(2, end);
ResultSet rs = stmt.executeQuery();
while (rs.next()) {
System.out.println(rs.getInt("empno") + ","
+ rs.getString("ename") + ","
+ rs.getDouble("sal") + "," + rs.getDate("hiredate"));}

        一直对rs.getxxx()的用法比较模糊，求介绍下用法        返回的结果集rs是不是既可以按列名rs.getxxx("xxx")也可以按rs.getxxx(1)这样读取啊？        另外上面的代码中