circular doubly linked list deletion at begining

 first node delete circular doubly linked list

public class cdll {
    class Node {
        int data;
        Node prev;
        Node next;

        Node(int data) {
            this.data = data;
            this.next = null;
            this.prev = null;
        }
    }
    Node head=null;
    Node tail=null;
    public void toadd(int data){
        Node newnode=new Node(data);
        if (head==null){
            head=newnode;
            tail=newnode;
            newnode.next=head;
            newnode.prev=tail;
        }
        else{
            tail.next=newnode;
            newnode.prev=tail;
            tail=newnode;
            tail.next=head;
            head.prev=tail;
        }
    }

    public void dis(){
        Node temp=head;
        if (head==null){
            System.out.println("empty");
        }
        else{
            do {
                System.out.println(temp.data);
                temp=temp.next;
            }while (temp!=head);
        }
    }
    public void delbeg(){
          Node temp=head;
          temp=temp.next;
          head=temp;
          head.prev=tail;
          tail.next=head;
    }
    public static void main(String[] args) {
        cdll cc=new cdll();
        cc.toadd(10);
        cc.toadd(20);
        cc.toadd(45);
        cc.toadd(70);
        cc.dis();
        System.out.println("*************");
        cc.delbeg();
        cc.dis();
    }
}