@Override public ReferenceEntry<K, V> peek() { ReferenceEntry<K, V> next = head.getNextInAccessQueue(); return (next == head) ? null : next; }
@Override @SuppressWarnings("unchecked") public boolean contains(Object o) { ReferenceEntry<K, V> e = (ReferenceEntry) o; return e.getNextInAccessQueue() != NullEntry.INSTANCE; }
@Override public int size() { int size = 0; for (ReferenceEntry<K, V> e = head.getNextInAccessQueue(); e != head; e = e.getNextInAccessQueue()) { size++; } return size; }
@Override protected ReferenceEntry<K, V> computeNext(ReferenceEntry<K, V> previous) { ReferenceEntry<K, V> next = previous.getNextInAccessQueue(); return (next == head) ? null : next; } };
@Override public boolean isEmpty() { return head.getNextInAccessQueue() == head; }
@Override public ReferenceEntry<K, V> poll() { ReferenceEntry<K, V> next = head.getNextInAccessQueue(); if (next == head) { return null; } remove(next); return next; }
@Override public void clear() { ReferenceEntry<K, V> e = head.getNextInAccessQueue(); while (e != head) { ReferenceEntry<K, V> next = e.getNextInAccessQueue(); nullifyAccessOrder(e); e = next; } head.setNextInAccessQueue(head); head.setPreviousInAccessQueue(head); }
@Override @SuppressWarnings("unchecked") public boolean remove(Object o) { ReferenceEntry<K, V> e = (ReferenceEntry) o; ReferenceEntry<K, V> previous = e.getPreviousInAccessQueue(); ReferenceEntry<K, V> next = e.getNextInAccessQueue(); connectAccessOrder(previous, next); nullifyAccessOrder(e); return next != NullEntry.INSTANCE; }
@Override public boolean offer(ReferenceEntry<K, V> entry) { // unlink connectAccessOrder(entry.getPreviousInAccessQueue(), entry.getNextInAccessQueue()); // add to tail connectAccessOrder(head.getPreviousInAccessQueue(), entry); connectAccessOrder(entry, head); return true; }
<K, V> void copyAccessEntry(ReferenceEntry<K, V> original, ReferenceEntry<K, V> newEntry) { // TODO(fry): when we link values instead of entries this method can go // away, as can connectAccessOrder, nullifyAccessOrder. newEntry.setAccessTime(original.getAccessTime()); connectAccessOrder(original.getPreviousInAccessQueue(), newEntry); connectAccessOrder(newEntry, original.getNextInAccessQueue()); nullifyAccessOrder(original); }