Spring：从Python中检索JSON数据

Question

的Python：

data = {
"id": 1,
"name": "Mike",
"passport":
    {
        "serial": "AM",
        "number": 1234
    }
}
r = requests.post("http://localhost:8080/save-json", data)

弹簧：

@RequestMapping(
        value = "/save-json",
        method = RequestMethod.POST)
@ResponseBody
public String saveJson(
        HttpServletRequest request) throws IOException, ServletException {
    Utils.logRequest(request, this.getClass());
    return body;
}

正文是：id=1&passport=serial&passport=number&name=Mike

requestDumperFilter显示：

method=POST
parameter=id=1
parameter=passport=serial, number
parameter=name=Mike

我错过了什么吗？我希望我制作了right json结构。