Error opening json file (Read only file?)

Question

Everytime I run the code I get java.io.FileNotFoundException: search.json: open failed: EROFS (Read-only file system)

here's the code

private static void writeJSearchKey(JSONObject obj) throws IOException {
        //write the searchKey value to the json file
        FileWriter file = new FileWriter("search.json");
        file.write(obj.toString());
        file.flush();
        file.close();
    }

and here's where the JSONObejct comes from (just for the sake of Context)

private static JSONObject writeJsonFile(String key) throws JSONException {
        //get searchInput string to JSON file
        JSONObject o = new JSONObject();
        o.put("searchKey", key);

        JSONObject newO= new JSONObject();
        newO.put("searchEngine", o);

        String oString= newO.toString();
        Log.d(TAG, oString);
        return newO;
    }