Extend KeyFilter facility to the whole cache

The key filter facility is very convenient for users who have multiple key types in the same cache. It would be very handy if this feature were extended to the whole cache.
e.g.

Cache<?, ?> cache = ...;
KeyFilter filter = ...;
Cache<K, V> view = cache.filter(filter);
view.addListener(listener) // Equivalent to the current cache.addListener(listener, filter) method
for (Map.Entry<K, V> entry: view.entrySet()) {
...
}