ExtJS中JSON数据传递乱码的解决

服务器环境：

Jetty 6.1.7

ExtJS-2.2

json-lib 2.2.2

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：

		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：

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