public com.google.cloud.vertexai.api.GenerateContentResponse.UsageMetadataOrBuilder
        getUsageMetadataOrBuilder() {
      if (usageMetadataBuilder_ != null) {
        return usageMetadataBuilder_.getMessageOrBuilder();
      } else {
        return usageMetadata_ == null
            ? com.google.cloud.vertexai.api.GenerateContentResponse.UsageMetadata
                .getDefaultInstance()
            : usageMetadata_;
      }
    }
<pre>
Usage metadata about the response(s).
</pre>

<code>.google.cloud.vertexai.v1.GenerateContentResponse.UsageMetadata usage_metadata = 4;
</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/GenerateContentResponse.java