How to parse Json data in android for Firebase Cloud Messaging (FCM)

Question

i am using FCM for push messages and handling all incoming push notification in onMessageReceived. Now the issue is with parsing nested json that comes inside this function remoteMessage.getData()

I have following block coming as a push notification in device. content of data payload could be varied here it is dealer later on it can be productInfo

{
  "to": "/topics/DATA",
  "priority": "high",
  "data": {
    "type": 6,
    "dealerInfo": {
      "dealerId": "358",
      "operationCode": 2
    }
  }
}

this how i am parsing it

 if(remoteMessage.getData()!=null){

        JSONObject object = null;
        try {
            object = new JSONObject(remoteMessage.getData());       

        } catch (JSONException e) {
            e.printStackTrace();
        }


    }

now i am getting data with blackslashes as remoteMessage.getData() returns Map<String,String> so probably my nested block is being converted in string not sure though.

{
  "wasTapped": false,
  "dealerInfo": "{\"dealerId\":\"358\",\"operationCode\":2}",
  "type": "6"
}

and if i write object = new JSONObject(remoteMessage.getData().toString()); then it got failed with following notification

{
  "to": "regid",
  "priority": "high",
  "notification" : {
      "body": "Message Body",
      "title" : "Call Status",
      "click_action":"FCM_PLUGIN_ACTIVITY"
   },
  "data": {
    "type": 1,
     "callNumber":"ICI17012702",
     "callTempId":"0",
      "body": "Message Body",
      "title" : "Call Status"
  }
}

error i get is

> org.json.JSONException: Unterminated object at character 15 of
> {body=Message Body, type=1, title=Call Status, callNumber=ICI17012702,
> callTempId=0}

Answer 1

try this code:

public void onMessageReceived(RemoteMessage remoteMessage)
    {
        Log.e("DATA",remoteMessage.getData().toString());
        try
        {
            Map<String, String> params = remoteMessage.getData();
            JSONObject object = new JSONObject(params);
            Log.e("JSON OBJECT", object.toString());
            String callNumber = object.getString("callNumber");
            //rest of the code
      }
   }

Also make sure your JSON is valid use This

Answer 2

Faced this issue when migrating from GCM to FCM.

The following is working for my use case (and OP payload), so perhaps it will work for others.

JsonObject jsonObject = new JsonObject(); // com.google.gson.JsonObject
JsonParser jsonParser = new JsonParser(); // com.google.gson.JsonParser
Map<String, String> map = remoteMessage.getData();
String val;

for (String key : map.keySet()) {
    val = map.get(key);
    try {
        jsonObject.add(key, jsonParser.parse(val));
    } catch (Exception e) {
        jsonObject.addProperty(key, val);
    }
}

// Now you can traverse jsonObject, or use to populate a custom object:
// MyObj o = new Gson().fromJson(jsonObject, MyObj.class)