presto-orc/src/main/java/io/prestosql/orc/metadata/OrcMetadataReader.java/OrcMetadataReader/toIntegerStatistics
class OrcMetadataReader:    private static IntegerStatistics toIntegerStatistics(OrcProto.IntegerStatistics integerStatistics)
    {
        return new IntegerStatistics(
                integerStatistics.hasMinimum() ? integerStatistics.getMinimum() : null,
                integerStatistics.hasMaximum() ? integerStatistics.getMaximum() : null,
                integerStatistics.hasSum() ? integerStatistics.getSum() : null);
    }