java实现链表修改节点问题

Question

代码如下：

public class LinkedList {
    public static void main(String[] args) {
        Node node = new Node(1, "zza", "tommy");
        Node node2 = new Node(2, "michael", "ma");
        Node node3 = new Node(3, "frank", "asd");
        List list = new List();
        list.add(node);
        list.add(node2);
        list.add(node3);
        list.show();
        list.exchangeInfo(1, "1", "1");
        list.show();
    }
}

class Node{

    String name;
    String nikeName;
    Integer no;
    Node next;

    public Node(Integer no, String name, String nickName) {
        this.name = name;
        this.no = no;
        this.nikeName = nickName;
    }

    @Override
    public String toString() {
        return "Node{" +
                "name='" + name + '\'' +
                ", nikeName='" + nikeName + '\'' +
                ", no=" + no +
                '}';
    }
}

class List {

    private Node head = new Node(null, null, null);

    public void add(Node node) {
        Node index = head;
        while(index.next != null) {
            index = index.next;
        }
        index.next = node;
    }

    public void show() {
        Node index = head.next;

        while(index != null) {
            System.out.println(index);
            index = index.next;
        }
    }

    public void exchangeInfo(int no, String name, String nickName) {
        if (head.next == null) {
            return;
        } else {
            Node index = head.next;
            boolean flag = false;
            while(true) {
                if (index == null) {
                    break;   // 链表遍历结束
                }
                if (index.no == no) {
                    flag = true;
                    break;
                }
                index = index.next;
            }
            if (flag) {
                index.nikeName = nickName;
                index.name = name;
            } else {
                throw new RuntimeException("没找到节点" + no);
            }
        }

    }

}

在上述代码中的链表修改节点的操作：

public void exchangeInfo(int no, String name, String nickName) {
        if (head.next == null) {
            return;
        } else {
            Node index = head.next;
            boolean flag = false;
            while(true) {
                if (index == null) {
                    break;   // 链表遍历结束
                }
                if (index.no == no) {
                    flag = true;
                    break;
                }
                index = index.next;
            }
            if (flag) {
                index.nikeName = nickName;
                index.name = name;
            } else {
                throw new RuntimeException("没找到节点" + no);
            }
        }

    }

在遍历链表中使用了一个指针用啦游走遍历：index，如代码所示，当遍历找到我们的需要修改的节点时，修改的操作是对index这个指针节点进行的，并没有对实际的节点进行操作，但是为什么最后得到的结果却是修改之后的结果呢？

Answer 1

什么意思，你这边就是进行修改了呀。