public com.google.protobuf.Struct getResponse() {
      if (responseBuilder_ == null) {
        return response_ == null ? com.google.protobuf.Struct.getDefaultInstance() : response_;
      } else {
        return responseBuilder_.getMessage();
      }
    }
<pre>
Required. The function response in JSON object format.
Use "output" key to specify function output and "error" key to specify
error details (if any). If "output" and "error" keys are not specified,
then whole "response" is treated as function output.
</pre>

<code>.google.protobuf.Struct response = 2 [(.google.api.field_behavior) = REQUIRED];</code>

@return The response.
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/FunctionResponse.java