You can convert your JsonArray or json string to ArrayList<OBJECT>
using Gson library as below
ArrayList<OBJECT> yourArray = new Gson().fromJson(jsonString, new TypeToken<List<OBJECT>>(){}.getType());
//or
ArrayList<OBJECT> yourArray = new Gson().fromJson(myjsonarray.toString(), new TypeToken<List<OBJECT>>(){}.getType());
Also while converting your ArrayList<OBJECT>
to JsonArray, no need to convert it to string and back to JsonArray
JsonArray myjsonarray = new Gson().toJsonTree(MyArrayList<OBJECT>).getAsJsonArray();
Refer Gson API documentation for more details. Hope this will be helpful.