public com.google.cloud.vertexai.api.ContentOrBuilder getContentsOrBuilder(int index) {
      if (contentsBuilder_ == null) {
        return contents_.get(index);
      } else {
        return contentsBuilder_.getMessageOrBuilder(index);
      }
    }
<pre>
Optional. Input content.
</pre>

<code>
repeated .google.cloud.vertexai.v1.Content contents = 4 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/CountTokensRequest.java