Add 1 to a number represented as linked list

class Solution
{
    
    public static Node reverse(Node head) {
         Node current=head;
        Node prev=null;
        while(current!=null) {
            Node tempNode = current.next;
            current.next=prev;
            prev=current;
            current=tempNode;
        }
        return prev;
    }
    
    public static Node addOne(Node head) 
    { 
       head = reverse(head);
        
        Node current=head;
        Boolean f=true;
        while(current!=null&&f==true) {
            if(current.data==9) {
                if(current.next!=null){
                    current.data=0;
                } else {
                    current.data=current.data+1;
                }
            }else{
                current.data=current.data+1;
                f=false;
            }
            current = current.next;
        }
        
        Node ans=reverse(head);
        // reverse back
      
        return ans;
    }
}