使用java中的方法交换单链表中的两个节点。

public class ListNode {
    int val;
    ListNode next;
    ListNode(int x) {
        val = x;
        next = null;
    }
}

public class SwapNodesInLinkedList {
    public void swapNodes(ListNode head, ListNode nodeA, ListNode nodeB) {
        if (head == null || nodeA == null || nodeB == null) {
            return;
        }
        
        // 找到待交换节点的前驱节点和后继节点
        ListNode prevA = null;
        ListNode prevB = null;
        ListNode curr = head;
        
        while (curr.next != null) {
            if (curr.next == nodeA) {
                prevA = curr;
            }
            if (curr.next == nodeB) {
                prevB = curr;
            }
            curr = curr.next;
        }
        
        if (prevA == null || prevB == null) {
            return;
        }
        
        // 交换节点
        prevA.next = nodeB;
        ListNode temp = nodeB.next;
        nodeB.next = nodeA.next;
        prevB.next = nodeA;
        nodeA.next = temp;
    }
}