public java.util.Map<String, String> getAdvancedOptions() {
        return advancedOptions;
    }
<p>
Only supports the <code>override_main_response_version</code> parameter and not other advanced options. You can
only include this option when upgrading to an OpenSearch version. Specifies whether the domain reports its
version as 7.10 so that it continues to work with Elasticsearch OSS clients and plugins.
</p>

@return Only supports the <code>override_main_response_version</code> parameter and not other advanced options.
        You can only include this option when upgrading to an OpenSearch version. Specifies whether the domain
        reports its version as 7.10 so that it continues to work with Elasticsearch OSS clients and plugins.
aws-java-sdk-opensearch/src/main/java/com/amazonaws/services/opensearch/model/UpgradeDomainRequest.java