@Override
    public int hashCode() {
        if (hashCode == 0) {
            hashCode = name.hashCode() * 31 + tags.hashCode();
        }
        return hashCode;
    }
Returns a newly-created instance whose name is concatenated by the specified {@code tags}.
core/src/main/java/com/linecorp/armeria/common/metric/MeterIdPrefix.java