public com.google.cloud.texttospeech.v1.SynthesisInput getInput() {
      if (inputBuilder_ == null) {
        return input_ == null
            ? com.google.cloud.texttospeech.v1.SynthesisInput.getDefaultInstance()
            : input_;
      } else {
        return inputBuilder_.getMessage();
      }
    }
<pre>
Required. The Synthesizer requires either plain text or SSML as input.
</pre>

<code>
.google.cloud.texttospeech.v1.SynthesisInput input = 2 [(.google.api.field_behavior) = REQUIRED];
</code>

@return The input.
java-texttospeech/proto-google-cloud-texttospeech-v1/src/main/java/com/google/cloud/texttospeech/v1/SynthesizeLongAudioRequest.java