RFR(s): 8201518 add test for randomized iteration order of unmodifiable Set and Map

[Stuart Marks]

On 5/24/18 2:20 AM, Peter Levart wrote:
> The test looks good, but the way you write keys from unmodifiable map composed 
> of WORDS:
> 
>    84             Arrays.stream(WORDS)
>    85                   .collect(toUnmodifiableMap(word -> word, word -> ""))
>    86                   .keySet()
>    87                   .forEach(mapOut::println);
> 
> ...could actually randomize order because of the way the collector constructs 
> the unmodifiable map and not because of the unmodifiable map API itself: [...]

> So you should perhaps construct an Map.Entry[] form WORDS keeping encounter
> order and initialize the unmodifiable map from it directly.
It seems unlikely to become an actual problem, but it is a good point. It's 
probably wise to make creation of the map as explicit as possible.

I've replaced that code with the following:

   85             var map = Map.ofEntries(Arrays.stream(WORDS)
   86                                           .map(word -> Map.entry(word, ""))
   87                                           .toArray(Map.Entry<?, ?>[]::new));
   88             map.keySet()
   89                .forEach(mapOut::println);

Updated webrev:

     http://cr.openjdk.java.net/~smarks/reviews/8201518/webrev.1/

Thanks,

s'marks