RFR(s): 8060192: Add default method Collection.toArray(generator)

[Paul Sandoz]

> On 5 Dec 2017, at 11:19, Stuart Marks <stuart.marks at oracle.com> wrote:
> 
> 
> 
> On 12/5/17 10:47 AM, Paul Sandoz wrote:
>>  345      * <p>Suppose {@code x} is a collection known to contain only strings.
>>  346      * The following code can be used to dump the collection into a newly
>>  347      * allocated array of {@code String}:
>> Make it an API note? (same for toArray(T[])
> 
> Will do.
> 
>>  352      * @implSpec
>>  353      * The default implementation calls the generator function with zero
>>  354      * and then passes the resulting array to {@link #toArray(T[])}.
>> That’s reasonable. I pondered about being vague and specifying a value in the range if [0, size()), to allow wiggle room for using 0 or size().
> 
> No, I really think it has to be exactly zero. If the default were to choose some value K < size(), the collection size could change to be smaller than K after allocation but before the call to toArray(T[]), resulting in an array that is unexpectedly large.

Ah yes, concurrent collections.

Paul.

> 
>>  360      * @throws ArrayStoreException if the runtime type of any element in this
>>  361      *         collection is not assignable to the {@linkplain Class#getComponentType
>>  362      *         runtime component type} of array returned by the generator function
>> s/of array returned by the generator function/of the generated array/ ?
> 
> Will do.
> 
> s'marks