A modern programming language that makes developers happier.

kotlinlang

But I’m wondering does it make sense to implement `equals()` for a non-`final` class in Java at all then?

Look at Enum’s equals() :slightly_smiling_face:

Generally speaking, typical classes should be final.

Unless you are very strict and reject sub-classes 
```
if(!getClass().equals(o.getClass())) return false;
```

Yes agree but there are cases when it is not practical. An example is Realm where a proxy class which is a sub-class of your model is created and it is an instance of the proxy class that is returned by queries etc

I would still like to get the boilerplate-free features of data classes without some of the restrictions.

Yes, thought about proxies too. Collections also define their own equals(), but they obey a general contract.

But thanks for pointing out the transitivity of equals(). I have something to think about now :slightly_smiling_face: