java - 链表设置引用

Question

谁能解释一下为什么temp.setNext(current.getNext());已经用过，不太明白

public void add(Object data, int index)
        // post: inserts the specified element at the specified position in this list.
        {
                Node temp = new Node(data);
                Node current = head;
                // crawl to the requested index or the last element in the list,
                // whichever comes first
                for(int i = 1; i < index && current.getNext() != null; i++)
                {
                        current = current.getNext();
                }
                // set the new node's next-node reference to this node's next-node reference
                temp.setNext(current.getNext());
                // now set this node's next-node reference to the new node
                current.setNext(temp);
                listCount++;// increment the number of elements variable
        }

Answer 1

您希望将新节点(由 temp 变量引用)插入到 index 位置处的节点之前，该位置在 while 循环完成后由 current.getNext() 引用。

因此，首先将 temp 的下一个节点设置为 current.getNext() (temp.setNext(current.getNext());)，然后将 current 的下一个节点设置为 temp (current.setNext(temp);)。这会将 temp 置于 current 和原始 current.getNext() 之间。

之前:

... -> current -> current.getNext() -> ...

之后:

... -> current -> temp -> current.getNext() (the original current.getNext()) -> ...