while循环里重复调用resultset的问题
while(true) {
try {
//建立连接
Connection new_conn =JdbcUtil.myconn();
PreparedStatement new_ps = null;
ResultSet new_rs = null;
String find_stu="select * from student where id=?";
new_ps=new_conn.prepareStatement(find_stu);
System.out.println(id);
new_ps.setObject(1, id);//id为字段名为id的字段
new_rs=ps.executeQuery();
//while(true)的循环循环到第二次这里就进不去了,result取出的结果集为空？？？
while(new_rs.next()) {
System.out.println("1.学生学号："+new_rs.getInt(2));
System.out.println("2.学生姓名："+new_rs.getString(4));
System.out.println("3.学生性别："+new_rs.getString(5));
System.out.println("4.学生年龄："+new_rs.getInt(6));
System.out.println("5.学生电话："+new_rs.getLong(7));
/**
* 展示该学生已选课程
*/
}
System.out.println("0.返回");
System.out.print("返回请输入0，修改某一项请输入修改项的序号");
int opr_num;
opr_num = in.nextInt(); in.nextLine();
switch (opr_num) {
case 1:
Change.change_stunum(sec_num);
break;
case 2:
Change.change_stuname(sec_num);
break;
case 3:
Change.change_stusex(sec_num);
break;
case 4:
Change.change_stuage(sec_num);
break;
case 5:
Change.change_stuphone(sec_num);
break;
case 0:
flag=false;
break;
default:
break;
}
if(flag==false) break;
}
catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally {
}
}
