Android：Volley ServerError响应代码400

Question

我正在尝试将json数据发送到fcm服务器URL，当我从fcm发送通知时，我收到默认通知，并且我的自定义通知未显示。我想实现这个，以便调用我的onMessageReceived()。每次我尝试发送时都会收到此错误。

04-11 13:39:22.244 21208-26145/com.myapp E/Volley: [28124] BasicNetwork.performRequest: Unexpected response code 400 for https://fcm.googleapis.com/fcm/send/
04-11 13:39:22.244 21208-21208/com.myapp E/!_@@_Errors--: com.android.volley.ServerError

这就是我所拥有的，

private void sendFCMPush() {

    final String Legacy_SERVER_KEY = getResources().getString(R.string.google_api_key);
    String msg = "this is test message,.,,.,.";
    String title = "my title";
    String token = "MY_TOKEN";

    JSONObject obj = null;
    JSONObject objData = null;
    JSONObject dataobjData = null;

    try {
        obj = new JSONObject();
        objData = new JSONObject();

        objData.put("body", msg);
        objData.put("title", title);

        dataobjData = new JSONObject();
        dataobjData.put("text", msg);
        dataobjData.put("title", title);

        obj.put("to", token);
        //obj.put("priority", "high");

        obj.put("notification", objData);
        obj.put("data", dataobjData);
        Log.d("!_@rj@_@@_PASS:>", obj.toString());
    } catch (JSONException e) {
        e.printStackTrace();
    }

    JsonObjectRequest jsObjRequest = new JsonObjectRequest(com.android.volley.Request.Method.POST, API_URL_FCM, obj,
            new com.android.volley.Response.Listener<JSONObject>() {
                @Override
                public void onResponse(JSONObject response) {
                    Log.e("!_@@_SUCESS", response + "");
                }
            },
            new com.android.volley.Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {
                    Log.e("!_@@_Errors--", error + "");
                }
            }) {
        @Override
        public Map<String, String> getHeaders() throws AuthFailureError {
            Map<String, String> params = new HashMap<String, String>();
            params.put("Authorization", "key=" + Legacy_SERVER_KEY);
            params.put("Content-Type", "application/json; charset=utf-8");
            return params;
        }
    };
    RequestQueue requestQueue = Volley.newRequestQueue(this);
    int socketTimeout = 1000 * 60;// 60 seconds
    RetryPolicy policy = new DefaultRetryPolicy(socketTimeout, DefaultRetryPolicy.DEFAULT_MAX_RETRIES, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT);
    jsObjRequest.setRetryPolicy(policy);
    requestQueue.add(jsObjRequest);
}

我一直在尝试不同的方式，但它们都不适合我。请帮帮我。