presto-elasticsearch/src/main/java/io/prestosql/elasticsearch/client/ElasticsearchNode.java/ElasticsearchNode/ElasticsearchNode
class ElasticsearchNode:    public ElasticsearchNode(String id, Optional<String> address)
    {
        this.id = requireNonNull(id, "id is null");
        this.address = requireNonNull(address, "address is null");
    }