Proposal: Comparables.isCommutativelyComparable
Doug Lea
dl at cs.oswego.edu
Sun Jun 9 14:09:54 UTC 2013
On 06/08/13 21:52, Martin Buchholz wrote:
> On Sat, Jun 8, 2013 at 8:50 AM, Doug Lea <dl at cs.oswego.edu
> <mailto:dl at cs.oswego.edu>> wrote:
>
>
> Suppose you have two objects, x and y, both of the same
> type (x.getClass() == y.getClass()) and both known
> to be instanceof Comparable.
>
> Can you compare them? That is, can you safely call
> (Comparable)x).compareTo(y);
>
>
> Probably others tried and gave up, because you cannot actually get a reliable
> answer - you can only get YES NO DUNNO, because some of the generic type
> information you need may have been erased.
Right, including the case where the class itself was declared with
raw types. I should have stated that the method spec should say
that a true return means YES, a false return means "not validated
under best effort".
-Doug
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