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

为什么改了head,temp也会变？？java存储是怎么分配的，head和temp算同一个对象吗？