从服务器获得字符串是出现中文乱码

使用Jetty服务器用JSON进行数据传递，发现中文字符都呈现????状乱码，response的头设置为：



Java代码 
response.setHeader("Pragma", "no-cache");   
response.setHeader("Cache-Control", "no-cache");   
response.setHeader("Expires", "0");   
response.setHeader("Content-Type", "text/xml; charset=utf-8");   
  
PrintWriter out = response.getWriter();  
response.setHeader("Pragma", "no-cache"); response.setHeader("Cache-Control", "no-cache"); response.setHeader("Expires", "0"); response.setHeader("Content-Type", "text/xml; charset=utf-8"); PrintWriter out = response.getWriter();


后为解决此问题添加了一行制定编码格式的语句，response.setCharacterEncoding("utf-8"); 解决问题时的代码：