On 05/14/2015 03:24 PM, Remi Forax wrote:
On 05/14/2015 03:05 PM, Brian Goetz wrote:
Not only is there a problem with modCount, but also with
equals/hashCode/toString. You can’t define these Object methods in
an interface.
They could be defined as static methods to delegate to. From API
consistency perspective, we have for example the following static
methods on primitive wrapper classes:
Right. We considered this during Lambda, but by the time we got
here, we concluded that this was mostly trading one downside for
another. It seemed overwhelmingly likely that people would forget to
override equals/hashCode/toString in this case, and create
collections that violated the contract.
That's a good reason.
The other problem is that it creates ambiguous method references,
if you have a class or an interface like:
class A {
public static int hashCode(A a) { ... }
}
A::hashCode is ambiguous.
Ah, I see. Then Integer::hashCode is ambiguous too if the target
functional interface takes boxed Integer parameter.
Regards, Peter
cheers,
Rémi
