presto-geospatial-toolkit/src/main/java/io/prestosql/geospatial/serde/GeometrySerde.java/GeometrySerde/merge
class GeometrySerde:    @Nullable
    private static Envelope merge(@Nullable Envelope left, @Nullable Envelope right)
    {
        if (left == null) {
            return right;
        }
        if (right == null) {
            return left;
        }
        right.merge(left);
        return right;
    }