public Builder clearInput() {
      if (inputBuilder_ == null) {
        if (streamingRequestCase_ == 2) {
          streamingRequestCase_ = 0;
          streamingRequest_ = null;
          onChanged();
        }
      } else {
        if (streamingRequestCase_ == 2) {
          streamingRequestCase_ = 0;
          streamingRequest_ = null;
        }
        inputBuilder_.clear();
      }
      return this;
    }
<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