@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (streamingRequestCase_ == 1) {
      output.writeMessage(
          1, (com.google.cloud.texttospeech.v1beta1.StreamingSynthesizeConfig) streamingRequest_);
    }
    if (streamingRequestCase_ == 2) {
      output.writeMessage(
          2, (com.google.cloud.texttospeech.v1beta1.StreamingSynthesisInput) streamingRequest_);
    }
    getUnknownFields().writeTo(output);
  }
<pre>
Input to synthesize. Specified in all messages but the first in a
`StreamingSynthesize` call.
</pre>

<code>.google.cloud.texttospeech.v1beta1.StreamingSynthesisInput input = 2;</code>
java-texttospeech/proto-google-cloud-texttospeech-v1beta1/src/main/java/com/google/cloud/texttospeech/v1beta1/StreamingSynthesizeRequest.java