toArray

[Howard Lovatt]

I can't remember ever getting an ArrayStoreException and long ago stopped worrying about them. It is not a good cost benefit trade off to worry about them. Therefore suggest that Remi formulation is used with a Javadoc note saying you won't get type safety and therefore might get an ASE. 

Sent from my iPad

On 17/12/2012, at 2:09 AM, Remi Forax <forax at univ-mlv.fr> wrote:

> On 12/16/2012 04:01 PM, Brian Goetz wrote:
>> 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.
> 
> yes, it's pragmatic choice.
> Few years back, i realize that a lot of Java developers never seen an ArrayStoreException or have trouble to remember the last time they saw one.
> 
> Rémi
> 
>> 
>> 
>> 
>> 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
>