I think you should use iterator() instead of listIterator(). See the explanation here: http://mail.openjdk.java.net/pipermail/core-libs-dev/2018-April/052472.html
вт, 4 дек. 2018 г. в 12:23, Tagir Valeev <amae...@gmail.com>: > Hello! > > Thank you for your comments! > > Yes, deserialization will be broken if we assume that size is never 0. > Also we'll introduce referential identity Collections.nCopies(0, x) == > Collections.nCopies(0, y) which might introduce slight semantics > change in existing programs. Once I suggested to wire Arrays.asList() > (with no args) to Collections.emptyList(), but it was rejected for the > same reason: no need to introduce a risk of possible semantics change. > > I updated webrev with equals implementation and test: > http://cr.openjdk.java.net/~tvaleev/webrev/8214687/r2/ > Comparing two CopiesList is much faster now indeed. Also we can spare > an iterator in the common case and hoist the null-check out of the > loop. Not sure whether we can rely that JIT will always do this for > us, but if you think that it's unnecessary, I can merge the loops > back. Note that now copiesList.equals(arrayList) could be faster than > arrayList.equals(copiesList). I don't think it's an issue. On the > other hand we could keep simpler and delegate to super-implementation > if the other object is not a CopiesList (like it's implemented in > java.util.RegularEnumSet::equals for example). What do you think? > > With best regards, > Tagir Valeev. > On Tue, Dec 4, 2018 at 10:56 AM Stuart Marks <stuart.ma...@oracle.com> > wrote: > > > > > > >> I believe it makes sense to override CopiesList.equals() > > > Also: contains(), iterator(), listIterator() > > > > equals(): sure > > > > contains() is already overridden. Not sure there's much benefit to > overriding > > the iterators. > > > > s'marks >
