Hi Charlie, Thanks for taking the initiative on this one. My recommendation would be to document all such areas, and then open it up for consensus on the convention to follow. I think @Jackie Jiang<mailto:xaji...@linkedin.com> has done similar cleanup in the past (specific to Nonnull vs Nullable<mailto:nulla...@microsoft.com>), would be good to build up on that.
I do agree with Kishore though, we should not trade for performance (specifically in query execution), and keep that in mind when discussing. Cheers, Mayank ________________________________ From: Charlie Summers <char...@gomerits.com> Sent: Saturday, May 9, 2020 9:25 PM To: d...@pinot.incubator.apache.org <d...@pinot.incubator.apache.org> Subject: Preconditions, Annotations, Exceptions, Nulls, and Optionals Hey Pinot team, My name is Charlie Summers and I'm a new contributor to the project. As I've started diving into the code, I'm not seeing a consistent pattern for how we handle unexpected behavior in the project. In some places we're throwing exceptions. In some places we log an error message then continue, returning a Null if a value is expected and having calling code handle the Null. When handling Nulls, we sometimes use @Nullable and @NotNull annotations and sometimes use Preconditions.checkNotNull(). I was chatting a bit with Kishore about this in Slack - he didn't have a strong preference for how to handle these things but was concerned about the performance implications of over-using Annotations and Precondition checks. What are all of your feelings on the matter? Personally I'm a fan of throwing Exceptions should state truly be exceptional instead of limping on and then handling a Null later. Where there's a need for a partially-functioning state or values may genuinely not be present, I'm a fan of Optionals (about their performance: https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fstackoverflow.com%2Fquestions%2F34696884%2Fperformance-of-java-optional%2F34697019&data=02%7C01%7Cmshrivas%40linkedin.com%7C10831b986b9647b5e19e08d7f49a3fce%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637246815649018974&sdata=bE%2FzJcow6K9VFmyzewNjmiuqP2REm8CgulR6PtTkV2g%3D&reserved=0 ). What have you all found to be effective? And definitely let me know if there is a more consistent standard that I'm missing because I've only just started dabbling with the code base. Cheers, Charlie Summers
