HttpServletResponse response = ServletActionContext.getResponse();
response.setCharacterEncoding("utf-8");
response.setContentType("text/xml;charset=utf-8");
response.setHeader("Cache-Control", "no-cache");
//确保在取得PrintWriter对象之前先设置response的编码;顺序搞错将无法解决中文乱码问题!
PrintWriter out = response.getWriter();