public Set<List<K>> keySet() {
    return ErasureUtils.<Set<List<K>>>uncheckedCast(keySet(new HashSet<Object>(), zeroKey, true));
  }
public Set < List < K > > keySet ( ) { return ErasureUtils . < Set < List < K > > > uncheckedCast ( keySet ( new HashSet < Object > ( ) , zeroKey , true ) ) ; }
Returns the set of keys, as read-only {@link List}s of size
equal to the depth of the GeneralizedCounter.