Merge Two Sorted Lists

/**
* 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) {
if(null == l1)
return l2;
else if(null == l2)
return l1;
ListNode head = new ListNode(0);
ListNode cur = head;
while(null != l1 && null != l2){
if(l1.val < l2.val){
cur.next = l1;
cur = l1;
l1 = l1.next;
}else{
cur.next = l2;
cur = l2;
l2 = l2.next;
}
}
if(null == l1)
cur.next = l2;
else if(null == l2)
cur.next = l1;
return head.next;
}
}