How to use

shiftKeys

method

in

it.unimi.dsi.fastutil.longs.LongLinkedOpenHashSet

/**
 * Removes the first key in iteration order.
 * 
 * @return the first key.
 * @throws NoSuchElementException
 *             is this set is empty.
 */
public long removeFirstLong() {
  if (size == 0)
    throw new NoSuchElementException();
  final int pos = first;
  // Abbreviated version of fixPointers(pos)
  first = (int) link[pos];
  if (0 <= first) {
    // Special case of SET_PREV(link[first], -1)
    link[first] |= (-1 & 0xFFFFFFFFL) << 32;
  }
  final long k = key[pos];
  size--;
  if (((k) == (0))) {
    containsNull = false;
    key[n] = (0);
  } else
    shiftKeys(pos);
  if (n > minN && size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
    rehash(n / 2);
  return k;
}
/**

/**
 * Removes the the last key in iteration order.
 * 
 * @return the last key.
 * @throws NoSuchElementException
 *             is this set is empty.
 */
public long removeLastLong() {
  if (size == 0)
    throw new NoSuchElementException();
  final int pos = last;
  // Abbreviated version of fixPointers(pos)
  last = (int) (link[pos] >>> 32);
  if (0 <= last) {
    // Special case of SET_NEXT(link[last], -1)
    link[last] |= -1 & 0xFFFFFFFFL;
  }
  final long k = key[pos];
  size--;
  if (((k) == (0))) {
    containsNull = false;
    key[n] = (0);
  } else
    shiftKeys(pos);
  if (n > minN && size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
    rehash(n / 2);
  return k;
}
private void moveIndexToFirst(final int i) {

private boolean removeEntry(final int pos) {
  size--;
  fixPointers(pos);
  shiftKeys(pos);
  if (n > minN && size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
    rehash(n / 2);
  return true;
}
private boolean removeNullEntry() {