public List<LinkDTO> queryUser(String name) {
        conn = ConnDB.getConn();
        List<LinkDTO> list = new ArrayList<LinkDTO>();
        String sql = "select  Id,NickName,Others from tb_link where UserName = ?";
        try {
            ps = conn.prepareStatement(sql);
            ps.setString(1, name);
            rs = ps.executeQuery();
            while (rs.next()) {
                LinkDTO ldto = new LinkDTO();
                ldto.setId(rs.getInt("Id"));
                ldto.setOthers(rs.getString("Others"));
                ldto.setNickname(rs.getString("NickName"));
                list.add(ldto);
                     [color=#FF0000]session.setAttribute("user",ldto);[/color]
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            ConnDB.closeConn(conn);
        }
        return list;
    }

------解决方案--------------------
你不是都写了么，稍微加两句。。。

if (rs.next() ){
out.println(rs.getString("admin_psw"));//获取admin_psw
out.println(rs.getString("amin_sex "));//获取amin_sex  
out.println("你好，"+admin);
}

还有你的sql有点问题，改一下
String sql = "select admin_id,admin_psw,admin_sex from admin where admin_id='"+admin+"'";

------解决方案--------------------
你应该有个admin的实体类

String sql = "select admin_id,admin_psw.amin_sex from admin where admin_id='"+admin+"'";
ResultSet rs = sqlbean.executeQuery(sql);
if (rs.next() ){
//查询数据信息存在在实体类中,具体admin方法已实际为准
admin bean=new admin();
bean.setId（rs.getString("admin_id")）;
bean.setPsw(rs.getString("admin_psw));
bean.setSex(rs.getString("admin_sex"));
out.println("你好，"+admin);}
}
//将admin放在session中，取出时${admin.id}即可
request.setArrtibutre("admin",admin);

------解决方案--------------------
看着想新手
if (rs.next() ){
out.println(rs.getString("admin_psw"));//获取admin_psw
out.println(rs.getString("amin_sex "));//获取amin_sex  
out.println("你好，"+admin);
}这样就行了，不用看别的什么了   javabean  你现在用不到  demo什么的你也....

------解决方案--------------------
用 rs.getString("admin_sex") 就可以获取了！
request.setSession()放到这里
登录后你可以把得到的放到session 里面 然后 request.getSession（）取出来就可以了