For review -- Comparator combinators

[David M. Lloyd]

On 11/13/2012 09:41 PM, Brian Goetz wrote:
> The following is a webrev for proposed extension methods on Comparator
> (reverse and compose) as well as static combinator methods in
> Comparators for things like turning a T -> {Comparable,int,long,double}
> into a Comparator<T>.
>
>    http://cr.openjdk.java.net/~henryjen/webrevs/8001667.0/
>
> This allows things like:
>
>    people.sort(Comparators.comparing(Person::getName))
>
>    Comparator<Person> byLastFirst
>        = Comparators.comparing(Person::getLastName)
>                     .compose(Comparators.comparing(Person::getFirstName))
>
> Please review and comment.

I like the .compose notion in general, but wouldn't it be nice if you 
could also, as a special case, do something like this:

Comparitor<Person> byLastFirst = 
Comparators.comparing(Person::getLastName, Person::getFirstName);

Or at least:

Comparitor<Person> byLastFirst = 
Comparators.comparing(Person::getLastName).compose(Person::getFirstName);

-- 
- DML