InfiniteStreamRecognize example of realtime STT is not working

Question

In my local computer, I'm trying Google realtime STT with below example.

• https://github.com/GoogleCloudPlatform/java-docs-samples/blob/master/speech/cloud-client/src/main/java/com/example/speech/InfiniteStreamRecognize.java

Other examples in above link works well. InfiniteStreamRecognize related to realtime STT does not work.

Problem is that onResponse of responseObserver is not called at all. As a result, i can't get any translated texts. And No exception/error is raised.

    try (SpeechClient client = SpeechClient.create()) {
      ClientStream<StreamingRecognizeRequest> clientStream;
      responseObserver =
          new ResponseObserver<StreamingRecognizeResponse>() {

            ArrayList<StreamingRecognizeResponse> responses = new ArrayList<>();

            public void onStart(StreamController controller) {
              System.out.println("onStart");
              referenceToStreamController = controller;
            }

            public void onResponse(StreamingRecognizeResponse response) { <- This code is never called.
              System.out.println("onResponse");
              responses.add(response);
              StreamingRecognitionResult result = response.getResultsList().get(0);
              Duration resultEndTime = result.getResultEndTime();
              resultEndTimeInMS =
                  (int)
                      ((resultEndTime.getSeconds() * 1000) + (resultEndTime.getNanos() / 1000000));
              double correctedTime =
                  resultEndTimeInMS - bridgingOffset + (STREAMING_LIMIT * restartCounter);

Audio datas gathering by microphone are sent successfully by below code without any exception.

    while (true) { ..
             ...
            tempByteString = ByteString.copyFrom(sharedQueue.take());

            // System.out.println("add audio data");
            request =
                StreamingRecognizeRequest.newBuilder().setAudioContent(tempByteString).build();

            audioInput.add(tempByteString);
          }

          clientStream.send(request);
    }

1. Is there any solution ?
2. Is there additional environment setting ? ex) gRPC for java