Java for LeetCode 206 Reverse Linked List

    public ListNode reverseList(ListNode head) {
        if(head==null)
        	return null;
    	Stack<ListNode> stack =new Stack<ListNode>();
        ListNode temp=head;
        while(temp!=null){
        	stack.push(temp);
        	temp=temp.next;
        }
        head=stack.pop();
        temp=head;
        while(!stack.isEmpty()){
        	temp.next=stack.pop();
        	temp=temp.next;
        }
        temp.next=null;
        return head;
    }