### Question:
Captions implements CaptionClient { public void get(String videoId, String language, ResponseListener<Caption> captionResponseListener, ResponseErrorListener responseErrorListener) { RequestBuilder requestBuilder = new RequestBuilder() .stringRequest(response -> { if (!response.isEmpty()) { try { JSONObject jsonObject = new JSONObject(response); captionResponseListener.onResponse(captionJsonSerializer.deserialize(jsonObject)); } catch (JSONException e) { responseErrorListener.onErrorResponse(new ServerException("could not parse response ", e)); } } }) .setMethod(Request.Method.GET) .setUrl("/videos/" + videoId + "/captions/" + language) .setErrorListener(error -> { if (error.networkResponse.statusCode >= 500) { responseErrorListener.onErrorResponse(new ServerException("ServerException " + error.networkResponse.statusCode, error)); } else if (error.networkResponse.statusCode >= 400) { responseErrorListener.onErrorResponse(new ClientException("ClientException " + error.networkResponse.statusCode, error)); } }); requestExecutor.execute(requestBuilder); } Captions(RequestExecutor requestExecutor, CaptionJsonSerializer captionJsonSerializer); void upload(String videoId, String language, String captionPath, ResponseListener<Caption> captionResponseListener, ResponseErrorListener responseErrorListener); void get(String videoId, String language, ResponseListener<Caption> captionResponseListener, ResponseErrorListener responseErrorListener); void getAll(String videoId, ResponseListener<ArrayList<Caption>> captionsResponseListener, ResponseErrorListener responseErrorListener); void update(String videoId, String language, Caption caption, ResponseListener<Caption> captionResponseListener, ResponseErrorListener responseErrorListener); void delete(String videoId, String language, EmptyResponseListener emptyResponseListener, ResponseErrorListener responseErrorListener);  }### Answer:
@Test public void showCaption() { String videoId = "viSuccess"; String language = "fr"; captionClient.get(videoId, language, null, null); assertTrue(requestExecutor.getRequestBuilder().getUrl().endsWith("/videos/" + videoId + "/captions/" + language)); assertEquals(requestExecutor.getRequestBuilder().getMethod(), Request.Method.GET); }