AJAX 解决传中文乱码问题

<script type="text/javascript">
//http://www.w3school.com.cn/ajax/index.asp
var xmlHttp;
function getCN(obj)
{
var author = document.forms[0].u367766562624002.value;   //中文值
author=encodeURI(author);
author=encodeURI(author); //传送的值，2次转码。
try{
// Firefox, Opera 8.0+, Safari
xmlHttp=new XMLHttpRequest();
}catch (e){
//Internet Explorer
try{
xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
}catch (e){
//  IE6, IE5
try{
xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
}catch (e){
alert("您的浏览器不支持AJAX！");
return false;
}
}
}

xmlHttp.onreadystatechange=function(){
if(xmlHttp.readyState==4 && xmlHttp.status==200){

var result=xmlHttp.responseText;
document.forms[0].u367763762460602.value=result;
}
};
var url = "xzShow.do?show=getcn&uname="+author;
xmlHttp.open("POST",url,true);
xmlHttp.send(null);
}
</script>

public ActionForward execute(ActionMapping mapping, ActionForm actionform,
HttpServletRequest request, HttpServletResponse response,
SessionUser sessionuser) throws Exception {

response.setContentType("text/html");
response.setCharacterEncoding("GBK");
PrintWriter out = response.getWriter();
String uname=StringUtils.trim(request.getParameter("uname"));
uname=URLDecoder.decode(uname,"utf8");  //解码
System.out.println("-----"+uname);
if(!uname.equals("")){
out.print("你好");
}
out.close();
return null;
}