`A cat may look at a king,' said Alice.  `I've read that in
some book, but I don't remember where.'

  `Well, it must be removed,' said the King very decidedly, and
he called the Queen, who was passing at the moment, `My dear!  I
wish you would have this cat removed!'

  The Queen had only one way of settling all difficulties, great
or small.  `Off with his head!' she said, without even looking
round.

          entry.getHash(),
          entry.getValueReference().get(),
          entry.getValueReference().getWeight(),
          RemovalCause.COLLECTED);
      writeQueue.remove(entry);
      accessQueue.remove(entry);
    }

    /** Removes an entry whose key has been garbage collected. */
    @CanIgnoreReturnValue
    boolean reclaimKey(ReferenceEntry<K, V> entry, int hash) {
      lock();
      try {

    map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

    map.put(two, three);
    map.remove(two, three);
    assertNotified(listener, two, three, RemovalCause.EXPLICIT);

    map.put(three, four);
    Iterator<?> i = map.entrySet().iterator();
    i.next();
    i.remove();
    assertNotified(listener, three, four, RemovalCause.EXPLICIT);

    map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

    map.put(two, three);
    map.remove(two, three);
    assertNotified(listener, two, three, RemovalCause.EXPLICIT);

    map.put(three, four);
    Iterator<?> i = map.entrySet().iterator();
    i.next();
    i.remove();
    assertNotified(listener, three, four, RemovalCause.EXPLICIT);

    assertThat(future.isDone()).isFalse();
    assertThat(executedRunnables).isEmpty();
    assertThat(pendingRunnables).hasSize(1);
    pendingRunnables.remove(0).run();
    assertThat(future.isDone()).isTrue();
    assertThat(executedRunnables).containsExactly(runnable);
    assertThat(pendingRunnables).isEmpty();
  }

    assertThat(future.isDone()).isFalse();
    assertThat(executedRunnables).isEmpty();
    assertThat(pendingRunnables).hasSize(1);
    pendingRunnables.remove(0).run();
    assertThat(future.isDone()).isTrue();
    assertThat(executedRunnables).containsExactly(runnable);
    assertThat(pendingRunnables).isEmpty();
  }

          entry.getHash(),
          entry.getValueReference().get(),
          entry.getValueReference().getWeight(),
          RemovalCause.COLLECTED);
      writeQueue.remove(entry);
      accessQueue.remove(entry);
    }

    /** Removes an entry whose key has been garbage collected. */
    @CanIgnoreReturnValue
    boolean reclaimKey(ReferenceEntry<K, V> entry, int hash) {
      lock();
      try {

    }

    @Override
    public boolean remove(@CheckForNull Object o) {
      try {
        return super.remove(o);
      } catch (UnsupportedOperationException e) {
        for (Entry<K, V> entry : map().entrySet()) {
          if (Objects.equal(o, entry.getValue())) {
            map().remove(entry.getKey());
            return true;
          }
        }

  `A cat may look at a king,' said Alice.  `I've read that in
some book, but I don't remember where.'

  `Well, it must be removed,' said the King very decidedly, and
he called the Queen, who was passing at the moment, `My dear!  I
wish you would have this cat removed!'

  The Queen had only one way of settling all difficulties, great
or small.  `Off with his head!' she said, without even looking
round.