public com.google.common.util.concurrent.ListenableFuture<com.google.longrunning.Operation>
        synthesizeLongAudio(com.google.cloud.texttospeech.v1.SynthesizeLongAudioRequest request) {
      return io.grpc.stub.ClientCalls.futureUnaryCall(
          getChannel().newCall(getSynthesizeLongAudioMethod(), getCallOptions()), request);
    }
<pre>
Synthesizes long form text asynchronously.
</pre>
java-texttospeech/grpc-google-cloud-texttospeech-v1/src/main/java/com/google/cloud/texttospeech/v1/TextToSpeechLongAudioSynthesizeGrpc.java