public String getEngineVersion() {
        return this.engineVersion;
    }
<p>
Version of OpenSearch or Elasticsearch that the domain is running, in the format <code>Elasticsearch_X.Y</code>
or <code>OpenSearch_X.Y</code>.
</p>

@return Version of OpenSearch or Elasticsearch that the domain is running, in the format
        <code>Elasticsearch_X.Y</code> or <code>OpenSearch_X.Y</code>.
aws-java-sdk-opensearch/src/main/java/com/amazonaws/services/opensearch/model/DomainStatus.java