Array equality, comparison and mismatch

[Paul Sandoz]

> On 5 Oct 2015, at 17:35, Chris Hegarty <chris.hegarty at oracle.com> wrote:
> 
> Paul,
> 
> On 22/09/15 17:30, Paul Sandoz wrote:
>> Hi,
>> 
>> Please review the following which adds methods to Arrays for performing equality, comparison and mismatch:
>> 
>>   https://bugs.openjdk.java.net/browse/JDK-8033148
>>   http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8033148-Arrays-lexico-compare/webrev/
>>   http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8033148-Arrays-lexico-compare/specdiff/overview-summary.html
> 
> This looks very good.
> 
> I know that there has been some discussion already about the behavior when passed null, but it seems a little unfortunate that the range accepting 'equals' methods don't behave in a similar manner to that of the non-range 'equals' methods. But I do accept that it makes little sense, where would the from/to indices come from. So I think NPE makes sense for these.
> 

Note that this consistent with other range accepting methods, such as on Arrays or Spliterators (which also usually throw null on the non-range methods too, i wish we could be consistent in that aspect).


> It was not immediately obvious to me that the common prefix can be 0. Should this be called out specifically?
> 

When reading the documentation of compare or mismatch or both?


> Minor typo(s):
> 
>  "...the length of the smaller array and it follows THAT the
>   index is only valid ..."
> 
>  "If one array is a proper prefix of the other, over the specified
>   ranges, then the returned relative index is the length of the
>   smaller range and it follows THAT the relative index is only valid
>   for the array with the larger range.”
> 

Fixed.

Thanks,
Paul.