private void buildPartial0(
        com.google.cloud.texttospeech.v1beta1.SynthesizeSpeechRequest result) {
      int from_bitField0_ = bitField0_;
      int to_bitField0_ = 0;
      if (((from_bitField0_ & 0x00000001) != 0)) {
        result.input_ = inputBuilder_ == null ? input_ : inputBuilder_.build();
        to_bitField0_ |= 0x00000001;
      }
      if (((from_bitField0_ & 0x00000002) != 0)) {
        result.voice_ = voiceBuilder_ == null ? voice_ : voiceBuilder_.build();
        to_bitField0_ |= 0x00000002;
      }
      if (((from_bitField0_ & 0x00000004) != 0)) {
        result.audioConfig_ =
            audioConfigBuilder_ == null ? audioConfig_ : audioConfigBuilder_.build();
        to_bitField0_ |= 0x00000004;
      }
      if (((from_bitField0_ & 0x00000010) != 0)) {
        result.advancedVoiceOptions_ =
            advancedVoiceOptionsBuilder_ == null
                ? advancedVoiceOptions_
                : advancedVoiceOptionsBuilder_.build();
        to_bitField0_ |= 0x00000008;
      }
      result.bitField0_ |= to_bitField0_;
    }
<pre>
The top-level message sent by the client for the `SynthesizeSpeech` method.
</pre>

Protobuf type {@code google.cloud.texttospeech.v1beta1.SynthesizeSpeechRequest}
java-texttospeech/proto-google-cloud-texttospeech-v1beta1/src/main/java/com/google/cloud/texttospeech/v1beta1/SynthesizeSpeechRequest.java