Rotate List

This is No.61 in leetcode.

The description:
Given a linked list, rotate the list to the right by k places, where k is non-negative.

This is my original solution:

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode() {}
 *     ListNode(int val) { this.val = val; }
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
 * }
 */
class Solution {
    public ListNode rotateRight(ListNode head, int k) {

        if (k == 0){
            return head;    
        }

        //ListNode tail = head;
        ListNode cur = head;

        // cur -> 3
        int count = 1;
        while (count <= k && cur !=  null) 
        { 
            cur = cur.next; 
            count++; 
        } 

        if (cur == null){
            return head;
        }

        ListNode tail = cur;

        while(cur.next != null){
            cur = cur.next;
        }

        /*
        // tail -> 4
       tail = cur.next;

        // 1 - 2 - 3 - 4 - 5 - 1
        tail.next = head;

        //4 - 5 - 1 - 2 - 3
        cur.next = NULL;
        */

        cur.next = head;
        head = tail.next;
        tail.next = null;

        return head;
    }
}

It could pass some tests, but here is a wrong case when the k is greater than the length of list, for example:

Input
[0,1,2]
4
Output
[0,1,2]
Expected
[2,0,1]

Then I fix my code as below:

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode() {}
 *     ListNode(int val) { this.val = val; }
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
 * }
 */
class Solution {
    public ListNode rotateRight(ListNode head, int k) {

    if(head == null || k == 0) {
        return head;
    }

    ListNode cur = head;

    int len = 1;

    while(cur.next != null) {
        cur = cur.next;
        len++;
    }

    cur.next = head;

    k %= len;

    for(int i = 0; i < len - k; i++) {
        cur = cur.next;
    }

    head = cur.next;
    cur.next = null;

    return head;
    }
}

Then it works.
By the way, here are two takeaways:

1. use node.next rather than node->next in java.
2. remember to use remainder.