public Iterator<K> iterator() {
return new KeySetIterator<K, V>((Iterator) elements.iterator());
}
public boolean remove(Object o) {
throw new NotYetImplementedException();
}
public boolean removeAll(Collection<?> c) {
throw new NotYetImplementedException();
}
public boolean retainAll(Collection<?> c) {
throw new NotYetImplementedException();
}
public int size() {
return elements.size();
}
public Object[] toArray() {
throw new NotYetImplementedException();
}
public <T> T[] toArray(T[] a) {
throw new NotYetImplementedException();
}
};
}