How about Collections.emptySorted[Set|Map] ?

[assembling signals]

Hello, everyone!

In the Collections utility class we have

* emptyMap()
* emptySet()

* unmodifiableSet(...)
* unmodifiableMap(...)
* unmodifiableSortedSet(...)
* unmodifiableSortedMap(...)

So we have no

* emptySortedMap()
* emptySortedSet()

I have several times encountered situations where methods needed either 
SortedSet or SortedMap.

Do you think in would be appropriate to introduce the two proposed methods?

Best regards,
Ivan G Shevchenko.