Issues with generic type detection of SAM types implemented using lambdas

[Oliver Gierke]

> Am 11.01.2018 um 14:56 schrieb David Lloyd <david.lloyd at redhat.com>:
> 
> On Thu, Jan 11, 2018 at 3:10 AM, Oliver Gierke <ogierke at pivotal.io> wrote:
>> Lambda based implementations of SAM types currently don't support inspecting the type for generic type parameters. This can cause unexpected surprise...
> 
> Here's a non-lambda example that demonstrates that inspecting *any*
> class for generic type parameters is fragile and not a good idea:
> 
> public final class Hasher<T> implements ToIntFunction<T> {
>    int applyAsInt(T value) { return value.hashCode(); }
> }
> 
> Oops, now all my concrete implementations have generic parameters.

I'm afraid I can't follow.

> Telling users they cannot have generic parameters on their
> implementation classes is poor API design.

Who is actually doing that?

Cheers,
Ollie

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