[Springframework-developer] Comparator singletons MIA?

[Oliver H. <Ol...@ou...>]

Jurgen,=20

I've just started upgrading Spring Rich to the latest spring code base
and noticed that all of the Comparator singletons (which Spring Rich
uses a lot) in the o.s.util.comparator package have been removed.=20

These classes are IMHO perfect examples of where you should be using a
singleton. Given that every instance will exhibit exactly the same
behaviour, why would you ever want to have more that one instance of a
class like ComparableComparator? Also how much cleaner is this:

ComparableComparator.nullSafeInstance().compare(argument1, argument2)

to this?

new NullSafeComparator(new ComparableComparator(),
true).compare(argument1, argument2)

and more performant to boot.

Anyway, obviously I can live without them, but I'm curious about the
rational behind the removal?=20

Thanks,

Oliver