+1 If we don't have a hierarchy of serializers then this method has no right to exist.
Cheers, Till On Wed, May 16, 2018 at 11:06 AM, Timo Walther <twal...@apache.org> wrote: > +1 > > TypeInformation has too many methods that need to be implemented but > provide little benefit for Flink. > > Am 16.05.18 um 10:55 schrieb Ted Yu: > > +1 from me as well. >> >> I checked a few serializer classes. The `equals` method on serializers >> contains the logic of `canEqual` method whose existence seems redundant. >> >> On Wed, May 16, 2018 at 1:49 AM, Tzu-Li (Gordon) Tai <tzuli...@apache.org >> > >> wrote: >> >> +1. >>> >>> Looking at the implementations of the `canEqual` method in several >>> serializers, it seems like all that is done is a check whether the object >>> is of the same serializer class. >>> We’ll have to be careful and double check all `equals` method on >>> serializers that may have relied on the `canEqual` method to perform the >>> preliminary type check. >>> Otherwise, this sounds good. >>> >>> On 16 May 2018 at 4:35:47 PM, Stephan Ewen (se...@apache.org) wrote: >>> >>> Hi all! >>> >>> As part of an attempt to simplify some code in the TypeInfo and >>> TypeSerializer area, I would like to drop the "canEqual" methods for the >>> following reason: >>> >>> "canEqual()" is necessary to make proper equality checks across >>> hierarchies >>> of types. This is for example useful in a collection API, stating for >>> example whether a List can be equal to a Collection if they have the same >>> contents. We don't have that here. >>> >>> A certain type information (and serializer) is equal to another one if >>> they >>> describe the same type, strictly. There is no necessity for cross >>> hierarchy >>> checks. >>> >>> This has also let to the situation that most type infos and serializers >>> implement just a dummy/default version of "canEqual". Many "equals()" >>> methods do not even call the other object's "canEqual", etc. >>> >>> As a first step, we could simply deprecate the method and implement an >>> empty default, and remove all calls to that method. >>> >>> Best, >>> Stephan >>> >>> >
