LinkedList中Iterator的remove()方法

Question

谁能解释一下这个方法是如何工作的，通过。这个地方if (next == lastReturned)。我不明白在什么情况下 next 可以等于 lastReturned.

public void remove() {
        checkForComodification();
        if (lastReturned == null)
            throw new IllegalStateException();

        Node<E> lastNext = lastReturned.next;
        unlink(lastReturned);
        if (next == lastReturned)
            next = lastNext;
        else
            nextIndex--;
        lastReturned = null;
        expectedModCount++;
    }

感谢解答！

Answer 1

lastReturned也可以是next如果迭代器的previous方法刚刚被使用过：

public E previous() {
    checkForComodification();
    if (!hasPrevious())
        throw new NoSuchElementException();

    lastReturned = next = (next == null) ? last : next.prev; // <=====
    nextIndex--;
    return lastReturned.item;
}

所以在那种情况下（previous() 然后 remove()），重要的是 remove 将 next 设置为下一项 after[=24] =] 刚刚删除的那个，这就是 if (next == lastRemoved) 正在做的事情。

LinkedList中Iterator的remove()方法

Method remove() of Iterator in LinkedList

java

collections

listiterator