java 解析 Android josn 数据 request.getReader()获取不到值

控制台报 A JSONObject text must begin with '{' at character 0 求大神

{"device_id":"48:88:ca:38:aa:3d","model":"Lenovo TAB 2 A10-70F","password":"147455566","platform":"ad","sys_ver":"4.4.4","type":"2","user_account":"1","version":"1.4.1"}
这是 app 传的参数
用火狐传这个参数没毛病又返回值，用APP就报错