@io.grpc.stub.annotations.RpcMethod(
      fullMethodName = SERVICE_NAME + '/' + "SynthesizeLongAudio",
      requestType = com.google.cloud.texttospeech.v1beta1.SynthesizeLongAudioRequest.class,
      responseType = com.google.longrunning.Operation.class,
      methodType = io.grpc.MethodDescriptor.MethodType.UNARY)
  public static io.grpc.MethodDescriptor<
          com.google.cloud.texttospeech.v1beta1.SynthesizeLongAudioRequest,
          com.google.longrunning.Operation>
      getSynthesizeLongAudioMethod() {
    io.grpc.MethodDescriptor<
            com.google.cloud.texttospeech.v1beta1.SynthesizeLongAudioRequest,
            com.google.longrunning.Operation>
        getSynthesizeLongAudioMethod;
    if ((getSynthesizeLongAudioMethod =
            TextToSpeechLongAudioSynthesizeGrpc.getSynthesizeLongAudioMethod)
        == null) {
      synchronized (TextToSpeechLongAudioSynthesizeGrpc.class) {
        if ((getSynthesizeLongAudioMethod =
                TextToSpeechLongAudioSynthesizeGrpc.getSynthesizeLongAudioMethod)
            == null) {
          TextToSpeechLongAudioSynthesizeGrpc.getSynthesizeLongAudioMethod =
              getSynthesizeLongAudioMethod =
                  io.grpc.MethodDescriptor
                      .<com.google.cloud.texttospeech.v1beta1.SynthesizeLongAudioRequest,
                          com.google.longrunning.Operation>
                          newBuilder()
                      .setType(io.grpc.MethodDescriptor.MethodType.UNARY)
                      .setFullMethodName(
                          generateFullMethodName(SERVICE_NAME, "SynthesizeLongAudio"))
                      .setSampledToLocalTracing(true)
                      .setRequestMarshaller(
                          io.grpc.protobuf.ProtoUtils.marshaller(
                              com.google.cloud.texttospeech.v1beta1.SynthesizeLongAudioRequest
                                  .getDefaultInstance()))
                      .setResponseMarshaller(
                          io.grpc.protobuf.ProtoUtils.marshaller(
                              com.google.longrunning.Operation.getDefaultInstance()))
                      .setSchemaDescriptor(
                          new TextToSpeechLongAudioSynthesizeMethodDescriptorSupplier(
                              "SynthesizeLongAudio"))
                      .build();
        }
      }
    }
    return getSynthesizeLongAudioMethod;
  }
<pre>
Service that implements Google Cloud Text-to-Speech API.
</pre>
java-texttospeech/grpc-google-cloud-texttospeech-v1beta1/src/main/java/com/google/cloud/texttospeech/v1beta1/TextToSpeechLongAudioSynthesizeGrpc.java