RFR 7065380 : Allow Collections.sort to sort Collections.singletonList() result
vitalyd at gmail.com
Thu Mar 1 20:56:25 UTC 2012
Also some collections may not have an O(1) size().
Sent from my phone
On Mar 1, 2012 3:52 PM, "Vitaly Davidovich" <vitalyd at gmail.com> wrote:
> I thought so too initially but that's optimizing for empty or singleton
> collections which probably are an edge case? Adding a branch, polymorphic
> method call, and increasing bytecode size may not be worth it.
> Sent from my phone
> On Mar 1, 2012 3:25 PM, "Rémi Forax" <forax at univ-mlv.fr> wrote:
>> On 03/01/2012 08:50 PM, Mike Duigou wrote:
>>> Hello all;
>>> Currently Collections.sort() refuses to sort the lists which result from
>>> calling Collections.singletonList(). This makes some sense because the
>>> singleton lists are immutable but they are also alway sorted.
>>> This patch allows Collections.sort() to be used with empty and singleton
>>> lists of all types. A short circuit return is provided for lists of length
>>> 0 and 1 as they are already sorted.
>>> WEBREV: http://cr.openjdk.java.net/~**mduigou/7065380/0/webrev/<http://cr.openjdk.java.net/~mduigou/7065380/0/webrev/>
>>> For the unit test ignore the diffs and view the "New" file--webrev
>>> doesn't understand "hg copy".
>> Is it not better to check list.size() before calling toArray() ?
More information about the core-libs-dev