将字符串从jsp页传到servlet页时产生乱码，使用了类似于name=new String(name.getBytes("iso-8859-1"),"UTF-8"); 未能转码成功，仍然有乱码

代码集：web-jsp页

<form action="AdminServlet" method="get">

<fieldset style="width:48%; float:left;">

<!-- to make two field float next to one another, adjust values accordingly -->

<label>个人签名</label><%String sign=admin.getSign();if(sign==null){sign="";}%>

<input type="text" style="width:92%;" name="sign" value="<%=sign %>">

<footer>

<div class="submit_link"><input type="submit" value="Publish" class="alt_btn">

<input type="reset" value="Reset">

</div>

</footer>

</form>

代码集web-AdminServlrt

UserDAO userdao=new UserDAO();

User admin=new User();

String sign=request.getParameter("sign");

if (sign!=null) {

nickname=new String(nickname.getBytes("iso-8859-1"),"UTF-8");

admin.setSign(sign);

System.out.println(sign);

}

输出结果??????????????????·?????????????????????????????????????????Щ·????????????????Щ?????????????????????о??????????????????????????????·????????????????????????????????????????????????????????ν??????????????????????????????????????????????????????????