I think we discussed this a couple of weeks ago, but to reiterate my position: I think we should use annotations where they allow the compiler and ancillary tooling (e.g. FindBugs) to catch and prevent classes of errors. @Override seems like a pretty easy one to add, and has concrete examples of the kinds of errors it can prevent. We discussed @Nullable, @Threadsafe and others that may have more marginal utility, so we were a bit less prescriptive there. To sum up, I agree with Alex that @Override has enough utility to say we should use it by default.
Cheers, Derek On Fri, Jun 3, 2022 at 8:04 AM Dinesh Joshi <djo...@apache.org> wrote: > So your proposal is to always add override annotation? Or are there > situations where you don’t want to add them? > > > On Jun 3, 2022, at 6:53 AM, Alex Petrov <al...@coffeenco.de> wrote: > > > Hi everyone, > > In our style guide [1], we have a following statement: > > > Avoid redundant @Override annotations when implementing abstract or > interface methods. > > I'd like to suggest we change this. > > @Override annotation in subclasses might be annoying when you're writing > the code for the first time, or reading already familiar code, but when > you're working on large changes and have complex class hierarchies, or > multiple overloads for the method, it's easy to overlook methods that were > not marked as overrides, and leave a wrong method in the code, or > misinterpret the call chain. > > I think @Override annotations are extremely useful and serve their > purpose, especially when refactoring: I can change the interface, and will > not only be pointed to all classes that do not implement the new version > (which compiler will do anyways), but also will be pointed to the classes > that, to the human eye, may look like they're overriding the method, but in > fact they do not. > > More concrete example: there is an abstract class between the interface > and a concrete implementation: you change the interface, modify the method > in the abstract class, but then forget to change the signature in the > overriden implementation of the concrete class, and get a behaviour from > the abstract class rather then concrete implementation. > > The question is not about taste or code aesthetics, but about making > maintaining a large codebase that has a lot of complexity and that was > evolving over many years simpler. If you could provide an example where > @Override would be counter-productive or overly burdensome, we could > compare this cost of maintenance with the cost of potential errors. > > Thank you, > --Alex > > [1] https://cassandra.apache.org/_/development/code_style.html > > -- +---------------------------------------------------------------+ | Derek Chen-Becker | | GPG Key available at https://keybase.io/dchenbecker and | | https://pgp.mit.edu/pks/lookup?search=derek%40chen-becker.org | | Fngrprnt: EB8A 6480 F0A3 C8EB C1E7 7F42 AFC5 AFEE 96E4 6ACC | +---------------------------------------------------------------+
