Android checks whether the JSON response is empty

In the Android application, I need to check whether the JSON response is null. This is my code:

private void showJSON(String response) {
    String nombre = "";
    String direccion = "";
    String codigo = "";
    try {
        JSONObject jsonObject = new JSONObject(response);
        JSONArray result = jsonObject.getJSONArray(Config.JSON_ARRAY);
        JSONObject collegeData = result.getJSONObject(0);
        nombre = collegeData.getString(Config.KEY_NAME);
        direccion = collegeData.getString(Config.KEY_ADDRESS);
        codigo = collegeData.getString(Config.KEY_VC);
    } catch (JSONException e) {
        e.printStackTrace();
    }

    if (nombre.isEmpty()) {
        nombre = "AGENCIA NO ENCONTradA";
        textViewResult.setText("Agencia:\t" + nombre);
    }
    else {

        textViewResult.setText("Agencia:\t" + nombre + "\nDireccion:\t" + direccion + "\nCodigo:\t" + codigo);
    }
}

I tried:

if (nombre.isEmpty()) {

if (nombre == null) {

if (nombre == "") {

However, the application always displays the else part of the if condition. If there is no data from JSON, the output is always:

Agency: null invalid null codego: null

If there is data, the output is the correct output. Any help is welcome

resolvent:

In Android, please use textutils. Isempty() to check whether it is null. But I think in your case, nombre is not empty. String nombre = "null"; Maybe in your case