presto-accumulo/src/main/java/io/prestosql/plugin/accumulo/index/Indexer.java/MetricsKey/equals
class MetricsKey:        @Override
        public boolean equals(Object obj)
        {
            if (this == obj) {
                return true;
            }
            if ((obj == null) || (getClass() != obj.getClass())) {
                return false;
            }

            MetricsKey other = (MetricsKey) obj;
            return Objects.equals(this.row, other.row)
                    && Objects.equals(this.family, other.family)
                    && Objects.equals(this.visibility, other.visibility);
        }