toArray

[Brian Goetz]

This works if you're willing to throw static type safety out the window; 
we have no compile-time guarantee that U[] is compatible with elements 
of type T.



On 12/16/2012 5:30 AM, Remi Forax wrote:
> On 12/16/2012 01:08 AM, Brian Goetz wrote:
>> Seems that the minimally invasive version of toArray (that doesn't
>> propagate the horrible convention established by Collection, and yet
>> doesn't foist Object[] on users) is:
>>
>>   interface Stream<T> {
>>       Object[] toArray();
>>       T[] toArray(Class<T> clazz);
>>   }
>>
>> It is unfortunate to need the Object[] version at all.  However, code
>> that is generic in T might be passed a Stream<T> and not know what
>> class literal to use.  It is further unfortunate that we cannot say
>>
>>   <S super T> S[] toArray(Class<S> clazz)
>>
>> as then such code could say toArray(Object.class), but we cannot (this
>> is a limitation of generics.)
>>
>
> why not ?
>
> interface Stream<T> {
>        <U> U[] toArray(Class<U> clazz);
> }
>
> Rémi