/** Returns the previous entry in the access queue. */
  ReferenceEntry<K, V> getPreviousInAccessQueue();

  /** Sets the previous entry in the access queue. */
  void setPreviousInAccessQueue(ReferenceEntry<K, V> previous);

  /*
   * Implemented by entries that use write order. Write entries are maintained in a doubly-linked

    previous.setNextInAccessQueue(next);
    next.setPreviousInAccessQueue(previous);
  }

  // Guarded By Segment.this
  static <K, V> void nullifyAccessOrder(ReferenceEntry<K, V> nulled) {
    ReferenceEntry<K, V> nullEntry = nullEntry();
    nulled.setNextInAccessQueue(nullEntry);
    nulled.setPreviousInAccessQueue(nullEntry);
  }

  // Guarded By Segment.this

    @Override
    public ReferenceEntry<K, V> getPreviousInAccessQueue() {
      return previousAccess;
    }

    @Override
    public void setPreviousInAccessQueue(ReferenceEntry<K, V> previous) {
      this.previousAccess = previous;
    }

    private long writeTime = Long.MAX_VALUE;

    @Override
    public long getWriteTime() {

    @Override
    public ReferenceEntry<K, V> getPreviousInAccessQueue() {
      return previousAccess;
    }

    @Override
    public void setPreviousInAccessQueue(ReferenceEntry<K, V> previous) {
      this.previousAccess = previous;
    }

    private long writeTime = Long.MAX_VALUE;

    @Override
    public long getWriteTime() {