controller返回中文字符串，网页中文字符显示 “？？？”

@RequestMapping(value = "/test", method = RequestMethod.GET, produces = "text/plain;charset=UTF-8")
	@ResponseBody
	public String getSinfo(HttpServletRequest request,
			HttpServletResponse response) {
		response.setCharacterEncoding("utf8");
		response.setContentType("text/plain; charset=utf-8");
		String testJson = "{" + "'message': '信息'," + "'success': 'true',"
				+ "'result': {" + " 'id': 'ddd'," + " 'xxxx': {"
				+ "    'fssj': '2018-05-02 10:10:00'," + "   'fsdd': 'XX地方',"
				+ "'jb': '2级'" + "}" + "}" + "}";
		return testJson;
	}