@SuppressWarnings("unchecked")
  private K key(int i) {
    return (K) requireKeys()[i];
  }

  @SuppressWarnings("unchecked")
  private V value(int i) {
    return (V) requireValues()[i];
  }

  private int entry(int i) {
    return requireEntries()[i];
  }

  private void setKey(int i, K key) {
    requireKeys()[i] = key;
  }

  private void setValue(int i, V value) {