Returns a key-value mapping associated with the least key strictly greater than the given key, or null if there is no such key.

Parameters:

key

the key

Returns:  an entry with the least key greater than key, or null if there is no such key

Exceptions:

ClassCastException		if the specified key cannot be compared with the keys currently in the map
NullPointerException		if the specified key is null and this map does not permit null keys