java doubly linked list

package clink;
 // Double circular linked list 
public  class TestDoubleLink {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
    DoubleLink d1=new DoubleLink();
    /*for (int i = 0; i < 6; i++){
        d1.insertHead(i);
    }
    
    System.out.println("The linked list obtained by the header insertion method is: ");
    d1.show();
    
    System.out.println("==================================");*/
    for (int i = 5; i < 10; i++){
        d1.insertTail(i);
    }
    
    System.out.println( "The linked list obtained by tail insertion is: " );
    d1.show();
    
    System.out.println("==================================");
    d1.deleteEntry(5);
    System.out.println( "The linked list after deleting the specified data is: " );
    d1.show();
    /*d1.insertHead(5);
    d1.show();*/
    }

}
class DoubleLink{
    class Entry{
        int data;
        Entry next;
        Entry prio;
        
        public Entry(){
              this.data =-1;
              this.next=null;
              this.prio=null;
        }
        public Entry(int data){
              this.data =data;
              this.next=null;
              this.prio=null;
        }
    }
    private Entry head=null;
    public DoubleLink(){
        this.head=new Entry();
    }
    public void insertHead(int val){
        Entry entry = new Entry(val);
        entry.next=head.next;
        entry.prio=head;
        head.next=entry;
        if(entry.next!=null){
            entry.next.prio=entry;
        }
    }
    public void insertTail(int val){
        Entry cur=this.head;
        while(cur.next!=null){
            cur=cur.next;
        }
        Entry entry=new Entry(val);
        cur.next=entry;
        entry.prio = cur;
        
        }
    public void deleteEntry(int val){
        Entry cur = this.head.next;
        while(cur!=null){
            if(cur.data==val){
                cur.prio.next=cur.next;
                if(cur.next!=null){
                    cur.next.prio = cur.prio;
                }
                cur=cur.next;
            }
        }
    }
    public void show(){
        Entry cur=this.head.next;
        while(cur!=null){
            System.out.println(cur.data+"");
            cur=cur.next;
        }
        System.out.println();
    }
    
}