presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/metadata/Distribution.java/Distribution/Distribution
class Distribution:    public Distribution(long id, Optional<String> name, List<Type> columnTypes, int bucketCount)
    {
        this.id = id;
        this.name = requireNonNull(name, "name is null");
        this.columnTypes = ImmutableList.copyOf(requireNonNull(columnTypes, "columnTypes is null"));
        this.bucketCount = bucketCount;
    }