Leetcode: Merge Two Sorted Lists

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

Solution:

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) {
 *         val = x;
 *         next = null;
 *     }
 * }
 */
public class Solution {
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        ListNode dummy = new ListNode(0);
        ListNode pointer = dummy;
        ListNode pointerL1 = l1;
        ListNode pointerL2 = l2;
        while(l1!=null && l2 !=null)
        {
            if(l1.val < l2.val)
            {
                pointer.next= l1;
                l1 = l1.next;
            }
            else
            {
                pointer.next= l2;
                l2 = l2.next;
            }
            pointer = pointer.next;
        }
        if (l1 == null)
            pointer.next = l2;
        else
            pointer.next =l1;
        return dummy.next;
    }
}